Amy peered ahead into the gloom and frowned. She turned to the Doctor, who was fiddling with his sonic screwdriver beside her.
‘So what exactly am I looking out for, Doctor? An itsy-bitsy cute-looking alien or something a bit more, you know –’ she pulled a monster-style face, clawed at the air with her hands and stomped her feet.
‘Embarrassing?’ ventured the Doctor.
Amy scowled. ‘I was doing “scary”.’
She and the Doctor had now spent ten minutes or more searching the area under the South Stand. They had gained entry through a locked (but not for long) maintenance doorway. The Doctor had led the way into the murky forest of dark grey columns that lay beyond – the sturdy metal struts of the grandstand’s steel skeleton. He had kept his eyes fixed on the flickering tip of his sonic screwdriver. Amy had followed, ducking under crossbeams now and again, and trying not to stumble on the rough concrete underfoot. With only the glow of the sonic to light their way, it was fairly slow going. By now Amy thought they must have been right under the centre of the grandstand.
So far, there had been no sign of any alien creature.
‘Sorry, Pond,’ said the Doctor. ‘Haven’t a clue what it looks like, I’m afraid. All we know is that it’s some kind of Luck-sucker.’
‘Excuse me?’
‘A Luck-sucker. A neural parasite.’
‘Again, excuse me?’
The Doctor left off recalibrating his sonic screwdriver for a moment to give Amy his full attention. ‘We know that poor chap back in the gents had been on a remarkable run of good fortune prior to his death. Yes?’
Amy nodded.
‘After the run of luck he’d been having,’ continued the Doctor, ‘he must have been feeling on top of the world this morning. His blood would have contained unusually high levels of endorphins.’
‘Which are?’ said Amy. ‘In normal-person speak, please.’
‘Hormones which make you feel euphoric,’ explained the Doctor. ‘They generate the feel-good rush.’
‘Yup, remembering now!’ said Amy. ‘Eating chocolate makes you release them, right?’
‘Indeed – among other things. The point is, they’re linked with the sort of emotional high our friend must have been on. But my bio-scans picked up no trace of any recent endorphin surge. Quite the opposite, in fact – from my sonic readings, you would have thought the poor fellow hadn’t felt happy in days.’
‘So the guy was a bit of a misery.’ Amy gave a shrug. ‘Why has that got us hunting aliens?’
‘He wasn’t a bit of a misery, Amy. He must have felt delighted – ecstatic, even – when he won that horse-racing bet. But something drained every trace of that positive energy from his body.’
‘Our mystery alien?’
‘Exactly,’ said the Doctor. ‘I’ve come across several species that feed on the positive neural energy of others. Neural parasites. They target those experiencing high levels of good fortune and extremes of happiness, and drain the resulting positive energy from them. Some folk call them Happiness Vampires, or Luck-suckers.’
Amy shivered. ‘Sounds creepy. Kinda like the Dementors in Harry Potter.’
‘I suppose,’ replied the Doctor. ‘Some species only drain off small quantities of neural energy, then move on. The host is left relatively unharmed – just a little low-spirited. But others drain everything they can –’
‘And you end up dead in a toilet.’
‘Not necessarily in a toilet. But dead, yes.’
‘So that’s what we’re looking for?’ said Amy. ‘An alien Luck-sucker?’
‘And you’re sure it’s under here somewhere?’
‘Almost certain.’ The Doctor held up his sonic screwdriver. Its tip was pulsing regularly. ‘I’m picking up clear signs of non-human life-form activity. My sonic screwdriver detected them even back in the changing room.’
‘Couldn’t they be coming from rats or something?’ suggested Amy. ‘Or really big spiders?’ She paused. ‘On second thoughts, I might prefer a happiness-draining alien.’
‘No, it’s something non-terrestrial. Or I’m a Raxacoricofallapatorian.’
The Doctor slowly scanned the sonic screwdriver to his right. His face lit up as its tip flared brightly.
‘There! You see!’ The Doctor excitedly thrust the screwdriver towards Amy. ‘Look at that, Pond! If it was all just concrete and steel under here, I wouldn’t be getting a bio-thermal reading like that, now, would I?’
Amy hadn’t the faintest idea which bit of the sonic screwdriver she was supposed to be looking at. ‘Absolutely not,’ she said solemnly. ‘That would be silly.’
‘Come on!’ The Doctor turned to his right and strode away purposefully. ‘This way!’
Amy did her best to keep up, picking her way through the maze of metal girders as fast as she could – but she spotted one crossbeam a moment too late.
‘Ow!’ She stopped to nurse her head. She had hit it quite hard. ‘Arrrggh!’ she growled. ‘Whatever that wretched alien is, I wish it had picked a nicer place to hang out!’
The Doctor didn’t reply. He had come to an abrupt halt just ahead of her. He had suddenly become very still, and was peering ahead into the gloom.
‘Doctor?’
He turned, eyes sparkling. ‘You’ve put your finger right on it again, Pond,’ he whispered excitedly.
Amy looked defensive. ‘What?’ she hissed back, not sure why they were whispering. ‘I didn’t touch anything!’
‘No, I mean, look!’ The Doctor bundled her forward, and pointed into the gloom. ‘A place to hang out is exactly what they were after …’
Up ahead, about twenty metres or so from where she and the Doctor were standing, Amy could make out pale shapes amid the darkness. As she concentrated her gaze, the Doctor increased the intensity of his sonic screwdriver’s glow a little, to cast a bit more light.
Dangling from one of the higher crossbeams of the grandstand’s metal framework was a row of twenty or so large, sac-like pale grey objects. Each of the flabby capsules was nearly three metres long, and had a slight ribbing to its shape, like the body of a maggot. The sacs hung from the girder by thick bands of sticky-looking webbing. They glistened, as though wet.
Midway along the row, Amy saw two sacs that looked different from the rest: they were ripped from top to bottom, as though they had burst. She could see that they were empty inside, except for the almost luminous silvery ooze that coated their inner walls.
Amy flinched – one of the sacs next to the burst ones had twitched, as though something inside it had moved.
‘Look! There are more over there!’ hissed the Doctor.
Amy followed his gaze. Away to the left, a second row of grey sacs dangled from another grandstand beam. She could just make out more rows in the murk behind them, too. There must have been hundreds.
Amy had no idea what was inside the peculiar grey sacs – or, in the case of the two burst ones, what had been inside them. But she knew one thing for sure: they gave her the creeps.
Big time.