“I’m hoping for a normal day today,” Oz said. “A nice, boring day without any crazy adventures.”

“Me too,” Caydon said. “Boredom’s a treat after scaredom.”

Silver ran her plastic scanner across Lily’s cheese and tomato baguette. “OK, you can eat that.”

They were in the queue for lunch in the school canteen, the day after their meeting with the leftover stegosaurus. Yesterday afternoon they had gone back to school, and the rest of the day had been totally un-magic.

“Can you scan all my chips at once?” Caydon asked. “Or do you have to do them one by one?”

Silver giggled. “Don’t be daft.”

The dinner lady serving the chips was a lady called Maria, a calm person with grey hair, who everyone liked because she was never cross and gave big portions.

Caydon held out his plate to her. “Hundreds of chips, please.”

“OK, lovey.”

In between scooping up the chips and dropping them on Caydon’s plate, something happened to Maria’s face – it shrank and hardened, and her greyish eyes darkened to deepest black with depths of red.

The eyes looked intently into Caydon’s and his heart somersaulted. He tried to nudge Silver, but he couldn’t move or make a sound. The racket of the canteen cut out and a voice spoke, close to his ear.

“Caydon Campbell? Can you hear me? Have I got through?”

Silver’s scanner let out an urgent series of bleeps. She moved so quickly that Caydon couldn’t work out what she was doing – but suddenly she had a gun and she was pointing it at Maria.

Maria’s new face twisted in agony and bitter fury. “Let me go!”

Silver said, “Hallo, Twelvey.”

Caydon knew her now. Oz and Lily knew her. The canteen was as still and silent as a stopped film.

“So you thought you’d have another go at kidnapping the carriers,” Silver said. “Nice try.”

“It’s not what you think.” Twelvey was shaking inside Maria’s overall. “I want to come over to your side.”

“Why should we believe that?”

“I can help you. I have vital information about Alba’s next move. Please, Silver! I’m doing this for my husband and my daughter!”

“I think she’s telling the truth,” Lily whispered.

“It’s worth the risk if she knows anything about Alba,” Silver said. “This could be just the break we need. Listen, Twelvey – we’ll meet you out by the bins in five, but no funny stuff. Got that?”

“Thank you! You won’t be sorry!”

Twelvey’s face sagged and swelled – and suddenly she was Maria again, piling chips on Caydon’s plate as if nothing had happened. The racket started again and the children gaped at one another’s pale, stunned faces.

“Let’s go,” Silver said. “Put your trays down and follow me.”

Caydon kept hold of his plate of chips and started eating them while Silver was hurrying them all out of the busy canteen, hiding her gun in the droopy sleeve of her jersey. There was a fire door at the side of the school that led to a square of tarmac where the huge dustbins were kept, and where the teachers parked their cars. Silver pushed them all through this door.

“We’re not allowed here,” Lily said.

A tall, slim woman with black hair stepped out from behind one of the dustbins. It was Twelvey, in a tight, short blue dress.

“Are you alone? Is this a trap?”

“We’re not working for your horrible sisters, if that’s what you mean,” Silver said. “Tell us what you want.”

Twelvey glanced round anxiously and lowered her voice. “I want you to arrest me and I’ll tell you anything you like. But I must have twenty-four-hour protection, and immunity from prosecution—”

“I don’t have the power to promise anything,” Silver said. “If you come quietly I’m sure you’ll be looked after.”

“Hey, I’ve seen that dress before,” Caydon said, still eating his chips. “Ms Gupta was wearing it this morning – I hope you haven’t left her naked!”

Twelvey ignored him. She was staring at Silver, her face hungry with hope. “I’ll do anything, if you just let me see my husband and daughter. I must be with them to protect them from what is to come!”

 

“Alba makes all that fuss about her parenting classes,” Twelvey said, “and she’s the worst parent in the world. She doesn’t understand that normal mothers – even wicked ones – will do practically anything to protect their children. That’s why I’m here.”

The defecting witch had been brought to a secure SMU interrogation suite, in a bunker underneath the MI6 building beside the Thames. Oz, Lily and Caydon watched her warily, waiting for any sign that she might turn dangerous.

But Twelvey was quiet and calm, wearing handcuffs and drinking a mug of tea. She looked at J. “Do you agree to my conditions?”

“I suppose so,” J said. “You won’t be charged with any D33 crime you tell us about, and you and your family will have round-the-clock security. But I can’t just release you straight back into the community. I’m afraid you must have at least a year of Evil Management Classes.”

“Oh, great – two hours a week with a load of chain-smoking, recovering demons.” Twelvey sighed crossly. “OK.”

“Now tell us what we need to know.” J held up the huge metal key. “We know that this is the key to the secret dungeon of Gog and Magog.”

“Where did you find that?” Twelvey stared at it. “Alba’s looked everywhere.”

“We also know that Alba wants to free her sons. Because if they stop guarding London, we’re all doomed.”

“She doesn’t care what it takes to get power,” Twelvey said. “That’s why she thought I wouldn’t care about Ludo and Greta. Well, that was her big mistake. I don’t give a toot about all the other humans who are going to die in agonies – but these are MY humans!”

Oz and Lily felt each other’s fear, but they also felt the comfort of the other voice that had spoken to them when they were little. The magic in the room was very strong, and for a moment Lily had the strangest feeling – that somehow Daisy was looking after them.

J was stern. “Where is the dungeon?”

“I’m surprised you don’t know,” Twelvey said. “It was your lot that built it. I thought you kept records.”

“Many records have been lost.”

“The dungeon was such a long way underground that the Great Fire couldn’t touch it. After that they built the new place.”

“New place?” J asked sharply. “Come on, Twelvey! Where are the giants locked up?”

“Under that vulgar new cathedral.”

There was a silence. “You mean,” J said, “St Paul’s.”

“That’s not new,” Caydon said.

“It’s new to her.” J was calm, but pale and tense. “The present St Paul’s was built at the end of the seventeenth century, after the old one was burned in the Great Fire. You’ll understand why Gog and Magog were locked up there when I tell you that the head of the SMU, in the days of Charles II, was a certain Sir Christopher Wren.”

“That’s the same Sir Christopher Wren who designed the Monument,” Silver said. “He also designed St Paul’s.”

“That’s right,” said Twelvey. “You see, it all started when Alba found an ancient document at a car boot sale. It said that the king told Sir Christopher to design a new seal for the giants’ dungeon – a seal that could never be broken.”

“So the seal is somewhere inside St Paul’s,” Lily said.

Twelvey said, “The seal IS St Paul’s. It’s the whole building – like an enormous cork in an enormous bottle. Alba knew she’d never shift it. But now she’s found another time stitch.”

“That’s impossible,” J snapped. “We’ve sealed all of them.”

The defecting witch smiled nastily. “You don’t know about all of them. When the next Great Fire of London came along, St Paul’s didn’t burn down – but the time fabric was severely weakened. So Alba’s planning to slip through the dropped stitch and complete the job by burning the cathedral to the ground and freeing her sons.”

“But there hasn’t been another Great Fire,” Lily said. “She must be lying.”

“As a matter of fact,” J said, very quietly, “St Paul’s Cathedral narrowly missed being burned down on the night of the 29th December, 1940.”

“The Blitz,” Twelvey said. “A terrible firestorm raged over the City of London, but by some fluke the cathedral was saved.”

“It wasn’t a fluke!” snapped J. “It was the people of London who saved their cathedral.” He turned back to the children. “On the night of December 29th, 1940, German planes dropped thousands of firebombs on the City of London. The firestorm destroyed everything around St Paul’s – but not the cathedral itself. The prime minister, Winston Churchill, sent an urgent order that St Paul’s must be saved at all costs. The reason he gave was that it was such a powerful symbol of national pride and hope – but he must have known that Gog and Magog, the Keepers of the Seal, were locked up underneath the place, and that everything would be over for us if they got out.”

Twelvey shrugged. “Whatever. Alba says she’s going to destroy the cathedral and free her sons. She wants to bond with them, though I think she’s left it too late. She fostered them with a family of bears when they were toddlers, and she sent them expensive gifts but never saw them from one birthday to the next. I told you, she’s a shocking mother. Much worse than I was. How is Greta, by the way? Any sign of a husband yet?”

“Never mind Greta.” J was deeply shaken. He suddenly looked years older. “We need those giants to stay exactly where they are. Doesn’t Alba care that she’ll be unleashing the forces of darkness?”

“No,” said Twelvey. “Alba likes the forces of darkness.”

“Luckily, she doesn’t have any more of the carriers’ DNA,” J said thoughtfully. “And without that, the chocolate phoenix is about as much use as a chocolate teapot.”

“She’ll find some way of getting it,” Twelvey said. “She’s ever so determined.”

“Hang on – that means us, and our DNA,” Oz said. “She’ll have to kidnap us again.”

“Oh, yes,” Twelvey said. “It only went wrong last time because Caydon had that giveaway vision. Next time she won’t be stopped by armed commandos.”

“Next time they’ll have a bodyguard,” Silver said, giving the witch a scornful look. “Nobody’s going to kidnap the carriers on my watch.”

“All the same,” J said, “I’ll send Elvira to guard the baby.”

“Great,” Caydon said. “She’ll be totally safe with Gran. Look how she dealt with those dryads.”

“That was nothing to do with your gran,” Twelvey said.

“It was – we all saw her! Lily called her with Silver’s bell.”

Twelvey let out a sour cackle. “But it wasn’t your gran who answered. It was the little walnut tree in the middle of the grove.”

“That’s what Mrs Fladgate called Daisy!” Lily leapt up excitedly. “Do you mean Daisy drove them away?”

“There’s some very old magic around your part of north London,” Twelvey said. “It’s all tied up with that Roman temple in Seven Sisters. Now I’d like another cup of tea – all this betraying has made me very thirsty.”

“All right, you can go now.” J nodded to the two armed policewomen waiting beside the door. “Take her to the high-security unit.”

“You said I could see my daughter.”

“Greta will be allowed to visit you.”

“OK.” Twelvey was marched out of the room between the two policewomen, still clutching her teacup.

J said, “B62, please put these children into time training right away, and send for the talking animals. I don’t want to send them back to 1940, but it’s just as well to be prepared.”

“Yes, sir – are you all right?”

“Perfectly.” He took a deep breath and steadied himself against the table. “It’s just that I have rather personal reasons for wanting to keep D33 away from St Paul’s.”

Everyone was quiet until Lily asked, “Are we going back to school now?”

“No.”

“Oh. Are we going home?”

“Not yet, I’m afraid. You’re safest here, in the MI6 building.”

“Oh.”

“Are we staying the night?” Caydon asked. “Do we get government pyjamas?”

J stood up. “Children.” He looked at them all in silence for a moment. “This could be the most important job you ever do for your country. If you can’t find me when you come back, I want you to go straight to the prime minister and give him the secret code word – cabbage.”

They looked at each other doubtfully. Oz said, “Just ‘cabbage’? Will he know what it means?”

“He’ll know.”

“But where will you be?” Lily asked.

“That,” J said, “is a very good question. But I’m afraid I can’t say more. B62 will take you to the briefing room, where you’ll be issued with 1940s clothes, weapons, gas masks and everything else you’ll need if you have to make a sudden jump into the past. You never know what Alba’s planning to do next.”