"Like, for real, we're going to travel in the Spectrel this morning?" said Kevin.

"Yes, Kevin. This is 'for real', not some parallel universe. As you can see, David's Spectrel is in a Cold War bunker under Kingsway."

They were in the Doctor's basement looking at two projections, which occupied the middle of the room. One showed a three-dimensional representation of the secret complex, including the buildings immediately above it. Kevin was captivated by it: the detail was extraordinary. The other projection was a live three-dimensional feed from Ware's Spectrel.

"It's like that bit in Star Wars, innit?" said Kevin. "Like where R2D2 is showing Luke the recording by Princess Leia, when she's asking for help from Obi-Wan Kenobi."

"Nah," said Ware. "Surely it's more like the bit where they see the 3D model of the Death Star? Or the bit in Return of the Jedi when they see the Death Star coming into firing position round the forest moon of Endor."

"Yeah, or there's this bit in –"

"Can I just remind you that the reason we're able to mount this rescue mission at all is because I was doing my job, rather than gorging myself on contemporary human cinema?" snapped the Doctor.

Ware turned to Kevin and muttered, "To be fair, he did get a bit less sleep than the pair of us."

"So our Spectrels estimate that they'll have to be in close proximity for ten sidereal minutes to get the power transfer completed. Unfortunately, it looks like she's under some scrutiny. Now, that needn't necessarily be a problem just so long as I can get the connection back." The Doctor nodded towards his Spectrel and the projections vanished.

"Excuse me, Doctor. Do you mind if I ask a stupid question?"

"There's no such thing as a stupid question. Fire away, but make it quick."

"Like, if you're using this transdimensional feed, why can't you use it from a distance?"

"Good question. There are four forces. Gravity is the weakest, but it makes its presence felt at almost infinitely greater distances than the others. The ones that apply on a subatomic level are unimaginably stronger than gravity, but make their presence felt over almost infinitesimally small distances. They bind subatomic particles together, but as soon as those particles are a short distance away – even just a couple of radii of those particles – then they are much weaker. This is a bit like that. Got it?"

"Um. I think so."

"Well it's a bit like the way I can reach the lab in the Spectrel through my pocket. Does that make sense now?"

"Not really."

"That's because you've not done the Ph.D. in Astrophysics yet. I take it you're postponing your Nobel acceptance speech by another decade."

"Is he always this sarcastic?" Kevin asked Ware.

"Nah, he's going easy on you. His full sarcasm has been banned by intergalactic treaty."

"So," said the Doctor. "First rule of time: the sooner we start, the sooner we're back."

"Uh, another stupid question if I may," said Kevin.

"Go on."

"Like, can't we just go back in time and stop them from taking David's Spectrel?"

"No, not really."

"But why not?"

"Misuse of time travel."

"But I don't understand."

"That's because, not only have you failed to complete your Ph.D. in Astrophysics, you have neglected to read the Laws of Time Travel, to which David and I are both signatories and of which we are both enforcers. We can do this another way, and so we must. Or, if you want to put it another way, because I say so, Kevin. Now hop in."

Doctor How opened the door of the red telephone box and held it. Kevin looked at Ware and How. He looked at the inside. There was a telephone and a shelf, just as he would have expected to see in any other box on any British high street.

"Okay, me first," said David. "Been a while, ain't it?" he squeezed into the telephone box and glanced around. He took a firm step forwards and disappeared. He didn't disappear into the back of the box as if stepping behind a curtain – he just ceased to be there.

"But where is he?"

"My cousin Where is now elsewhere, if you'll indulge my humour."

"Yeah, but where?"

"Quite literally, he's nowhere. Nowhere so far as you're capable of experiencing at the moment. He doesn't exist anywhere you could experience him."

"Yeah, but isn't that dangerous? I mean, what if –"

"I haven't got time to talk hypotheticals and probabilities right now. Just do as he did and I'll follow."

Kevin stepped into the phone box and looked back at the Doctor, who waved him on impatiently. He took a step forward, and ceased to be.

He was at the side of a control room. He felt a sudden force in his back and was thrown forwards. A hand grabbed his hoodie from behind and stopped him from falling to the floor.

"Hell's bells, Kevin," said the Doctor. "What did you stop in the doorway for? You're like those bloody tourists who stop outside Tube stations and block the exit for everyone else. Stop rubbernecking and take a seat, lad."

Kevin glanced behind him. There was no door behind the Doctor that he could see.

"Leave it, Peter," said David. "It's his first time. No one's that confident their first time, are they?"

"Oh, I suppose," said the Doctor. "Sorry."

Kevin looked around the circular room. It was a brilliant white – so bright that it overwhelmed his eyes. He felt it should have been painful, but it was calming. In the centre of the room was a semi-circular control panel with a single seat. He moved towards it.

"No, not there," said the Doctor. "Passenger seat." He indicated one of several comfortable-looking black seats in rows around the side of the room.

"Come and sit beside me," said Ware. "And I'll answer any questions you might have."

"Why are there no seatbelts?"

"Not needed. Forget your preconceptions about travel. You're not travelling at all."

"Oh, but if we're not travelling..."

"Then how do we get there? Easy. I don't know how much Peter's explained to you."

"He told me it's all a bit like zip files and things."

"Hmm. This bit isn't. There are all these other dimensions that you don't – and, indeed, most of the Pleasant universe – doesn't experience on a day-to-day basis. That's mainly because most of them don't harbour life."

"Most?"

"Well, some do, by implication. Obviously."

"It might be obvious to you."

"If I say 'most don't', then some obviously do. Keep up, sunshine. So when we stepped into the Spectrel we stepped into a space elsewhere. If you were looking at it from any angle, it would always be going away from you to get there because it's always perpendicular to your own dimensions. Does that make sense?"

"Not really."

"Good. Nor should it, if you were being totally honest. Now, let me give you an analogy as to how this works, if you're interested." Kevin nodded. "So the Spectrel provides us with a door into that other space. We just close the door behind us in the Pleasant universe and then open it somewhere else. We've not really moved in this particular dimension, but we've changed the Cartesian coordinates of the door in the Pleasant universe."

"Uh. I think I get the analogy."

"Oh. Have you read Philip Pullman's His Dark Materials trilogy?" asked Ware.

"As a matter of fact, I read it when I was off school with 'flu. Someone sent me it from Amazon. I asked around but never found out who it was. Complete mystery. Amazing book, though — really blew my mind."

Across at the console, the Doctor stifled a smile.

"The Subtle Knife is about the best explanation of the physics I've read in your culture," said Ware. "Will is able to cut a hole into other universes. It's a bit like that. Except without the other universes. Oh, and we always close the doors behind us. Bit dangerous if you don't."

"So, like, where's the Spectrel? Are we tumbling through the Time Vortex?"

"For God's sake, don't let him catch you talking mumbo-jumbo like that. This Spectrel doesn't exist. None of them do."

"What? But we're in it."

"Sure, but it doesn't exist in your world. It's just a projection of forces. Did Peter at least explain to you that nothing is actually there where we think it is?"

"Um. Yes. Like a table isn't really composed of anything at all. It's just forces, with a tiny bit of matter."

"So it's not there. In the same way as nothing else is there."

"Yes, but how come we're able to exist in another dimension?"

Ware tapped the side of his nose. "Very good, Kevin. That's the secret the Time Keepers have which makes us the Time Keepers. The rest of the Pleasant universe would love to know."

"Well, why don't you tell them?"

"Mayhem. For all our many faults, we do see fit to abide by a strict set of Laws. We're respected for our adherence to them, and for our all-round goodness."

"Sorry to sound cynical, but that's, like, subjective, innit? One man's goody is another man's baddy."

Ware grinned. "Oh, no. No, Kevin. Believe me; you'll know the baddies when you meet them. You think some of the lads on your estate are bad 'uns? You don't wanna meet some of the nasty entities hanging around out there." Ware swept his hand in an arc.

"And what's this Pleasant universe you and the Doctor are always talking about?"

"If I say something like 'most of' and what's left over is therefore 'some of, but not all', then if I say Pleasant universe, then...?"

"Then there's an Unpleasant universe. And... and the Unpleasant universe is what doesn't make up the Pleasant universe?"

"Got it in one."

"But that still doesn't explain –"

"I think David has explained quite enough for now," said Doctor How.

"Are we there yet?" joked Ware.

The Doctor rolled his eyes and then addressed Kevin. "We've always been there. Unfortunately, time has moved whilst you've been yakking. You may have noticed that it has a tendency to do that. That movement of time has allowed events to unfold, as you can see." Above the control panel was a projection of the bunker in which the Spectrel was being held. Thickett and Peterson were visible in the gallery.

"As I said, he does sarcasm by the bucket," said Ware. "He could move into wholesale."

"But if we're already there, and if we've been there all along, why couldn't we charge David's Spectrel?" said Kevin, exasperated.

"Because we're still nowhere. We're all around this place, but we're at right-angles to it," said Ware.

"Then how will we get there?"

"Just open the door and we'll be there. You'll see."

"I'm sorry, this is making exactly no sense at all," said Kevin.

"I said leave it for now," said the Doctor. "David, I'll hold you personally responsible if the poor lad suffers a brain aneurysm. I should warn you that his mother is fearsome. Now, look at this."

"That's the MI16 agents," said Kevin. "She's well cute."

"And there was me thinking that it was just our giant beetle's sex-drive that would be a problem on this mission. She was at Imperial. Saw her there as a doctoral student. Peterson. Camilla. Good reputation. The other man is Thickett. Career civil servant. Exactly in the mould of others we've seen before in Sixteen. She'll be the one with the scientific mind and he'll be the odious pen-pusher."

They watched as the two men in NBC suits emerged from the armoured door under the viewing gallery.

"So what's the plan?" asked Ware. "This is your op."

"After we enter the chamber I need to reconnect the Spectrels. We'll jam all the security services' systems, of course –– doors and alarms. You two just need to keep those goons in the Noddy suits busy whilst I work my magic as a jump-start lead."

"Gotcha," said Kevin. "Like, how long do you need?"

"Maybe thirty seconds."

"That's actually quite a long time, Doc," said Kevin. "For example, to smash and grab from a car you've got five, max. A good shoplifting move is, like, two."

"Kids these days, eh?" said Ware. "Still, I'm glad you're an equal-opportunities employer and looking to fill that critical thieving skills gap so prevalent in the time-travelling community." He winked at Kevin. "It's alright Kevin. You know, his brother –"

"Leave my brother out of this, David. Please, be serious. I'm relying on you both to keep them busy for thirty seconds. That's all."

"What do you suggest we do?" asked Kevin.

"Oh, I don't know. Perform a comedy sketch, ask them what brand of shampoo they use, run around a bit or something. They won't be expecting us, so you'll take them completely by surprise. Now, come on, let's go to the door."

Doctor How walked to where he and Kevin had entered. A crack of darkness opened in the dazzling white of the wall and formed the shape of a doorway. Kevin stood directly behind him and Ware right behind Kevin. From the projection above the console they could hear Jackson cry out with pain as he touched the badge on the cab. Ware laughed. "That's my girl," he said.

"Okay," said Doctor How. "Double-quick. Go!"

The Doctor leapt forward and disappeared. Kevin took two quick steps and found himself in the concrete chamber, next to Ware's Spectrel. The two men in Noddy suits were just a few feet away and were looking up at the viewing gallery. He gawped for a second at the extraordinary transition he had made from nowhere to this place. Ware slammed into his back and he sprawled to the floor, which seemed to be shaking under his body.

"Don't you learn? Never stop in a doorway," said Ware, grabbing his hoodie and pulling him to his feet.

Kevin glanced around. Doctor How's red telephone box was glowing brightly right in front of the black cab. The Doctor had climbed up onto the bonnet and was stretching out to connect its badge with the crown on his own Spectrel using his hands as the contacts.

"That's them!" echoed Thickett's voice from a loudspeaker. It echoed around the chamber. The men in the Noddy suits turned and took a step back as they took in the sudden appearance of a glowing telephone box and three intruders in such a secure installation. "Get them! Arrest those three men!" yelled Thickett.

"Argh!" croaked Doctor How, as his hands connected the two Spectrels. His body shook and his hair stood on end.

The two men stepped towards Kevin, who began running. "It's not me you want – it's him!" said Kevin, gesticulating up at Thickett. "He's a paedo!"

"Metropolitan Police, Child Sexual Crimes Section," said Ware, standing his ground. "Mr Thickett is wanted for perverting the course of justice. And being a pervert."

"Urgh," gargled Doctor How.

The concrete floor shook again, enough to make the Doctor slip on the cab's bonnet and lose touch with the crown of his Spectrel. One of the men in Noddy suits fell over. Ware steadied himself against his Spectrel. Kevin tripped over a slab of concrete, which had been pushed up as cracks appeared in the floor. As he lay on the shaking concrete, the floor in front of him erupted in a spray of concrete and mud. He twisted his body just fast enough to dodge a chunk slamming down where he'd been lying. As he tried to get up he felt himself being lifted as the floor rose next to his head and left him at a forty-five degree angle. A pair of black mandibles sliced through the steel reinforcement embedded in the concrete, the slab jerked up to ninety degrees and he pushed back onto his feet. The stench of oil made his head swim.

A three-foot black antenna swished through the air and knocked him on the left side of his head, crushing the top of his ear against his skull. He felt blood on his hand, and ran back as the front end of a huge black creature emerged from the hole. The slab that Kevin had been lifted on slammed backwards onto the floor with a deafening bang which reverberated around the chamber. One of the creature's legs caught on a metal toolbox and its contents went flying, the tools ringing and clattering to the floor.

Doctor How took his position on the bonnet of the cab again. The two men in Noddy suits ran for the exit under the viewing gallery and hammered on the massive steel door.

"Yurgh! David. For God's sake, stun it with your Ultraknife," shouted the Doctor. "It's our only hope."

"I can't. It's in the glove compartment."

"Well, open your Spectrel and get it. Argh!" The Doctor's body jerked under the strain of the power coursing through his body between the Spectrels.

"No, it's in me cab what's back at your place."

"You left your...? EEE!"

The rest of the beast crashed through into the chamber, scattering more mud and pieces of concrete across the floor. The panicked men in Noddy suits stopped hammering at the exit, turned and stared in awe and terror, their backs pressed against the door.

"It was useful on the job. You know, tricky customers, starting the cab on a cold morning, that sort of thing."

"You idiot. Argh! You know you should never... Ugh! Misuse of......Oonf!"

"Give him your Ultraknife, Doctor!" screamed Kevin, as the beast turned and began to focus its attention on the humans and Time Keepers.

"I. Urgh! I can't. Security. It's in my pocket. Can't reach. Yerrgh!"

"You're bleedin' useless, the pair of you!"

"Get in the Spectrel," yelled the Doctor. "Turn the Taxi light on."

"She still won't let me in."

Jackson and the other man resumed their futile banging at the security door. "Get them!" Thickett screamed. "They control the creature. Do something!"

Jackson picked up a hammer which had fallen near his feet. He took aim and threw it at the creature's mouth. The hammer hit a set of inner mandibles and the creature hissed, turning its attention fully on the men in Noddy suits.

"Noooo!" screamed the Doctor.

It was too late – the creature lunged for the men, punching and ripping a hole in the steel door with a mandible. The Doctor jumped down from the bonnet and reached into his pocket. The creature jerked around and caught Jackson's leg with a mandible, slicing it off below the knee. The severed leg and foot arced up in the air and bounced off the window of the viewing gallery, smearing it with blood.

"Kill it, Doctor!" shouted Thickett.

"I can't!" shouted the Doctor. "It's petrochemical. We have no idea what happens when it dies – it could blow us all to smithereens!"

"The Taxi light just came on!" shouted Kevin. "I'll get its attention."

The creature was waving its antennae over Jackson, who lay paralysed, blood from his severed leg pouring out onto the floor.

Kevin ran from the cab and kicked the creature in the area where he thought its reproductive organs would be, then jumped back as it turned to face him. He vaulted the bonnet of the cab. The creature took in the information and hissed. The Doctor ran for Jackson. The creature hesitated, then nature took its course as it saw the amber light on top of the cab. It scuttled around the back of the Spectrel and began to mount it.

"You're going to be alright," said the Doctor to Jackson, who was losing consciousness. He took out a bandage from his pocket and tied a tourniquet above the man's knee. Jackson's colleague approached him, carrying a heavy spanner. "Drop it," said the Doctor. The man raised the spanner and the Doctor whipped out his Ultraknife and stunned him. The man fell to the floor. The clang of the spanner caused the creature to turn its attention back to Jackson and the Doctor.

"He's attacking our men!" shouted Thickett over the intercom.

"He's defending himself," protested Peterson.

"Well, why didn't he stun the creature?"

"It could blow up – don't you listen?"

All this time, Ware had been leaning back against the driver's door of his Spectrel, his palms spread on its flanks, strangely calm and passive. Now that the creature was mounting the rear of the cab, he edged away and turned his back to the Doctor, who was moving his Ultraknife back and forth across Jackson's bloody stump.

"Kevin, bring me that man's leg," said the Doctor.

Kevin looked at the creature, looked at Ware, then ran to get the severed leg from the corner of the chamber. The limb was still in its one-piece rubber trouser and boot. The ragged end of the rubber Noddy suit was smeared with blood. It was heavier than he'd thought it would be, and jiggled around in the boot in a sickening way as he jogged over to where the Doctor was kneeling beside the groaning Jackson and his unconscious colleague.

"Can you...?" asked Kevin.

"Maybe," said the Doctor. "It's a clean cut, but if I can just......" He peeled back the rubber from above the knee, and took the lower leg from its boot. "If I can just connect the major veins and arteries... bit tricky, even in the best of circumstances."

Kevin glanced around. The creature was absorbed in its act of passion. Ware had climbed onto the bonnet of the cab, just three feet from the creature's head. "Dave," he said under his breath, amazed at Ware's bravery.

The Doctor looked up and followed Kevin's gaze to see his cousin place the palm of his hand on the crown of the telephone box. "David! No! You're not fit enough."

"Cobblers. I feel like me old self, Peter. Just you watch this, me old China." Ware reached his palm down to the badge on the nose of the cab.

"No!" shouted the Doctor. "Get away from there!"

"I cannot deny my timeline," said Ware. "I am Where once more!"

Where's palm made contact and closed the connection between the two Spectrels. His scream sent a shock down Kevin's spine. In that instant Where's Spectrel vanished from beneath him. He fell, his head hit the floor with a thwack and his body went limp. The creature's impact with the concrete was louder. It paused for a couple of seconds then let out a loud hiss, its mouth just a couple of feet from Where's unconscious body.

"Where's his Spectrel gone?" asked Kevin.

"I haven't got time to explain." The Doctor glanced at his patient, then at the creature, which was turning its attention towards them again. "We have to get out of here, all of us. Now. Grab these and hold them tight."

Kevin took hold of Jackson's upper and lower leg and pushed them together.

"David, you bloody idiot," muttered the Doctor. He began creeping towards his fallen cousin.

"Doctor, how can we help?" asked Peterson over the intercom.

"Not stealing things you don't understand, for a start," he shouted back.

"What can we do now?"

The Doctor glanced around him. "If you can turn that amber traffic light on." He pointed to the set of lights by the exit to the surface.

"It's a trick," said Thickett. "He wants you to open the exit so that he can escape with his monster."

"It's not a trick," said Peterson.

"How do you know?"

"That thing is distracted by amber lights. Didn't you see? Now, get out of my way."

"Miss Peterson –"

"It's Doctor Peterson, Mr Thickett. In scientific matters you have to give way to my superior training. This, Mr Thickett, is just such a time."

"We will be talking about your conduct in this situation at your next performance review," seethed Thickett.

The Doctor continued creeping towards Where. The creature jerked to the right to bring its full attention on him. "Good boy," he said. "You don't like eating things."

Peterson began flicking switches up in the viewing gallery.

"No luck?" called the Doctor.

"I'm trying, I'm trying," said Peterson. "Keep it distracted."

"Easy for you to say."

The creature took a step towards the Doctor. He inched back, then began skirting around behind his Spectrel, away from Kevin and Jackson.

"Don't leave me, Doctor!" shouted Kevin.

"No one's abandoning you, Kevin," said the Doctor, continuing to circle round to the creature's right. "You're the least of my worries right now because you're doing very well."

He came back into the creature's view from behind his Spectrel. The creature shifted position once more to keep him in sight. "Oh, drat, double-drat, drat squared, and drat to the power of drat. You're not at all mesmerised by my Spectrel's light are you, my coleopteran cretin? Oh, who gave you a big body but kept your brain the size of pinhead? I would love to know. You're so brainless you could be a human politician." He kept on moving round and the creature shifted again to keep him in view.

"Can't you, like, shine an amber light from your Ultraknife?" said Kevin.

"Oh, thank you Kevin. I really hadn't thought of that."

"It's just that it can –"

"Well, it just can't flaming well do that. Alright?"

"Sorry, just trying to help."

The creature lunged at the Doctor, who leapt sideways as it slammed into the wall, sending a shower of concrete fragments rattling to the floor.

"It's not happy, Doctor Peterson."

"I can see that, Doctor," said Peterson. The sound of her desperately flicking switches was audible over the intercom.

The Doctor moved towards the main exit, which was as far away from his own Spectrel as he could be in the chamber without backing into a corner. He raised his Ultraknife as the creature began moving towards him again.

"Kevin, start dragging that chap over to the Spectrel, will you? Put your hands under his shoulders and drag him."

"He's going to take a hostage," said Thickett. "I'll make sure he gets fifteen years for that."

Kevin pulled Jackson towards the telephone box. The severed lower leg was now hanging on to the upper part of the limb by a couple of shreds of tissue.

"Got it!" said Peterson.

The Doctor heard a click above him and glanced up at the traffic light. "You're colour-blind, Doctor Peterson – that's green."

"I'm nearly there."

The beast hunkered down on its feet, ready to leap forwards again at the Doctor. He held up his Ultraknife and braced himself. "I don't want to do this, beastie," he said softly. "It might hurt all of us as much as it'll hurt you."

Click.

The beast jumped, the Doctor dived, rolled to the side and scrabbled to his feet, his Ultraknife still pointing at the beast. The creature had leapt onto the wall and was caressing the amber light with its antennae.

"Okay, Kevin, let's go!" shouted the Doctor. He ran to help Kevin pull Jackson the last couple of yards to the door of the telephone box. "We need to get David. Hurry."

They each put their hands under one of Where's armpits and pulled with all their might to drag him next to Jackson. "If he recovers, he's going on a diet immediately," gasped the Doctor. "Now, get that man into the Spectrel."

On the other side of the chamber, Jackson's colleague staggered to his feet, taking in the situation. He bent down to pick up his heavy spanner again.

The Spectrel's door swung open. Kevin got behind Jackson's head and pulled him the last couple of feet into the Spectrel. They disappeared and the door closed.

"See that?" gasped Thickett. "Kidnapping."

"Right, come on, you big lump," said the Doctor, grabbing his cousin under the armpits. The Spectrel's door opened again.

Jackson's colleague lumbered towards the Doctor and raised the spanner.

The Doctor fumbled for his Ultraknife and jabbed at it. The man collapsed and the spanner clanged to the floor. "Sorry!" said the Doctor. With a loud grunt he pulled his cousin into the Spectrel and disappeared. The door closed.

Peterson and Thickett looked at each other, then back down at the chamber. The creature was halfway up the wall next to the main exit, grinding its lower body against the surface. The other member of their team was lying unconscious in his Noddy suit on the floor. The chamber itself was a wreck – a gaping hole towards one corner, and damage to the wall in a couple of places.

"I don't know what you propose to do now, Miss Peterson," said Thickett.

"What I intend to do, Mr Thickett? You chose to take Where's Spectrel."

"How am I going to explain this to the minister?" wailed Thickett. "And what do we do with the creature? Our communications are still jammed. We're helpless."

"He's still here," said Peterson.

The red telephone box continued to glow in the chamber below.

"He's still got our internal communications jammed," said Thickett.

"I doubt there's much anyone could do to help us."

The door of the Spectrel opened again, and the Doctor stepped out and glanced around. "Look, sorry about the mess. Technically it's not my fault. This thing – or maybe these things plural, are after either my cousin or me. We don't know why. They seem to home in on the signal from a weakened Spectrel. Bit of an own goal, bringing one here after my cousin's Spectrel had been pinpointed by whoever it is. I do hope you're insured."

"What are we going to do about that creature?" asked Peterson.

"I've not seen it go quite that long. Oh, there we go." Fluid splashed onto the wall beneath the creature. A few drops hit the armoured steel door to its left, and the metal hissed. "Quick, turn the light off!"

Peterson turned off the amber light. The creature lay motionless on the wall.

"I think we can save your man Jackson's leg," said the Doctor. "He'll probably have a hell of a limp."

"That's kidnapping. I'm going to have you for that, Doctor How. I know what you're up to – you're going to interrogate him under duress and steal our secrets."

"Oh, please, Mr Thicko –"

"It's Thickett, and I'm proud of it."

"I can't imagine what you might possibly think you have that's worth knowing that I don't know already, or couldn't find out if I could be bothered to spend a nanosecond hacking your systems, Mr Thicky."

"Thickett!"

"Whatever. Look, we'll pop Jackson somewhere safe. Probably a bit later today, if that's alright."

"Where?" asked Thickett.

"Tsh. Can't have you knowing my movements in advance, Mr Twit."

The creature began to stir.

"For the last time, it's Thickett. That... that thing could break into the control room. We have to stop it. You have to get rid of it, Doctor. I'll hold you personally responsible for this."

"Really, it'll get bored in a minute. Needs a post-coital snackette. It'd be great if you had some volatile petroleum products," said the Doctor. "Look, if it's okay with you I'll be off for now. But I'd be grateful if you could go back to defending the Realm from those who would do harm to Her Brittanic Majesty's citizens, or whatever it is you're supposed to be doing, rather than hassling harmless helpers."

The creature dropped to the floor. The Doctor stepped into the Spectrel and raised his hand to wave.

"It's going to get Smith!" said Thickett. "Turn that light back on!"

"No!" shouted Peterson and the Doctor simultaneously.

Thickett pushed Peterson out of the way and flicked the switch.

Click.

The Spectrel's door slammed shut and it winked out of existence. Peterson jumped on top of Thickett, slamming him onto the floor of the control room, pinning him to it with her body.

The departure of the Spectrel took the jamming from the control room's systems, which began to reboot. An old-fashioned steady alarm-bell rang, and a modern siren warbled into life.

Nothing happened for a couple of seconds. Peterson raised her head a fraction, and Thickett opened his mouth to reprimand her. If they had been able to see out of the control room, they would have seen that something had happened. If they'd turned their heads to the monitors, they would have seen them wink into life just in time to show the last two seconds of images that they would ever display.

The creature's acid ejaculate had melted through the wiring of the traffic light. There had been a spark as the light had been turned on, and a small flame had been ignited. It flashed down the wall and licked around the posterior of the creature, where fluid still dripped from its failed congress. The creature breathed out through the spiracles in its abdomen, and a yellow flame lit off the breath that came out of two on its right side, like a couple of miniature flares from an oil refinery. The twinge of pain made it breathe in sharply with shock. Deep inside the tubes of the creature's respiratory system the flame found the perfect mix of oxygen and combustible vapour.

The explosion blew out the bullet-proof windows of the control room from their surrounds and a couple of pieces of burning black body casing and a mandible bounced off the far wall and hit the floor. Oily black smoke poured off the body parts as yellow-orange flames crackled furiously from them.

"Stay on the ground!" shouted Peterson. She crawled beneath the thickening layer of smoke to where she knew there was a fire extinguisher. She grabbed it and sprayed the fragments with inert powder.

The door burst open, and four Ministry of Defence firemen in breathing apparatus ran into the room. They pulled Thickett and Peterson out into the corridor, where a pair of medics clapped oxygen masks on their faces.

"Smith! Get Smith! He's in the chamber," shouted Peterson.

"How and Where!" said Thickett.

"This one's not making much sense," said one of the medics to a doctor, who had just arrived, out of breath.

"The Doctors! It was the Doctors!"

"Who?" asked the doctor.

"No! Not Who. How and Where!" said Thickett.

"Shock," said the doctor to the medics. "Just relax, sir," he said to Thickett. He took out a syringe and tapped it for bubbles as he squeezed the plunger. "Going to feel nice and sleepy now."

"No! Get Who, you nincompoop! Get the Doctors!"

"That's it," said the doctor. "I'm a doctor and I'm here now. Breathing deeply now, and going to sleep. Relaaaax. That's it."

A man arrived in a military Noddy suit. "Smith and Jackson," he panted. Where are they, Peterson?"

"Jackson's being looked after by the Doctor," said Peterson. "Smith...... Oh, God. Smith's down there, in the chamber."

"So this is Jackson?" said the doctor.

"No, that's Thickett," said Peterson. "Jackson had an accident, the Doctor... Oh, never mind." She turned to the man in the Noddy suit. "Smith was down there when the explosion happened."

"He's not there now," said the man in the Noddy suit. "No bodies. No human bodies."

"The Doctor must have come back for him. Thank God for that."

"Shock," said the doctor to the man in the Noddy suit. "She'll be fine. The other one was hysterical. Had to sedate him. Come on, Miss. Don't try to stand yet – we don't know what sort of damage you might have."

"It's Doctor," she said. "I'm a doctor. Well, not that kind of doctor. Not your kind of doctor – my kind of doctor."

"Oh, dear," said the doctor. He took out another syringe and tapped it for bubbles.

"No, that's really not necessary, doctor. I'm perfectly alright."

"Of course you are. How about a drink or dinner sometime?"

"Thank you, but I think I'm going to be extremely busy for the immediate future."