“Oh yes . . . This is the stuff to give the boys! It’s bad down here, but I’m the baddest thing in this station! Yes yes yes!” He broke into a soft-shoe routine, lost interest, realised JC was looking at him steadily, and giggled briefly. “On the job, JC! Oh yes! I’m getting something. I’m picking up all kinds of psychic traces, but only one original to this location that’s recent enough to qualify as a probable focal point. God, I feel lucid. Something happened right here, on this platform, within the last few days.”

“Are you . . . all right, Happy?” said Melody. “You don’t look too good.”

“I feel fine! Fine!”

“The sweat is pouring off your face, Happy,” said JC. “And your eyes . . .”

“I am in the groove!” said Happy. “Now shut up and let me work. Oh, I’m on fire now! Someone died here. Murdered. A young woman . . . robbed of so many years, so much future life. That’s a great source of power for whoever was responsible, all those potential years. Murder magic. Necromancy. Bad stuff.”

“Can you reach her?” said JC. “Can you contact her? Bring her here, make her manifest for us?”

“She’s coming,” said Happy. His face was flushed, he couldn’t stop grinning, and his eyes were fever bright. “Our life energies are drawing the murdered girl here. We blaze so brightly to her dead eyes, and so she comes to us out of the dark like a moth to a flame, or a child to a familiar, once-loved place. She’s almost here. Be gentle with her, JC. She doesn’t understand that she’s dead. She’s trapped in a half-way state, caught up in a dream that never ends. Never really aware of where she is, or what’s happening. Don’t try to wake her, JC. That would be cruel.”

He’d barely finished speaking when a young woman appeared suddenly out of nowhere, right there on the platform before them, standing with her back to them as though waiting for a train. She stood on the very edge of the platform, lost in her own thoughts, occasionally looking down the tracks at the tunnel-mouth, waiting for a train that would never come. She didn’t seem to notice JC or Happy or Melody. JC moved slowly, cautiously, forward until he was standing beside her, a polite distance away. She didn’t look at him. JC looked at her.

His first thought was how beautiful she was. A pre-Raphaelite dream of a woman in her late twenties, with a huge mane of glorious red hair tumbling down around a high-boned, sharply defined face. Her eyes were a vivid green, and her mouth was a bright red dream, with a smile tucked away in one corner. She wore a long white dress that clung tightly here and there to show off a magnificent figure. She seemed calm enough, real enough . . . so full of life, with so much still to live for. All the things she might have done, all the things she might have achieved . . . For a moment, JC couldn’t speak, overwhelmed with pain and rage at what had been done to her, at what she’d been so cruelly deprived of. He made himself look away and glanced back at Melody.

“Use the database of missing persons,” he said quietly. “Find her. I need to know her name, and exactly what happened. I need to know everything about her.”

“Way ahead of you,” said Melody. “I’m looking at the police report now, but there’s not much in it. Only the bare facts of her murder, death from a single stab wound . . . no witnesses, no suspects. Nothing here to suggest she was anyone important.”

“They’re all important,” said JC. “All the people, all the victims, who end up as ghosts. That’s why we do this.”

“This is an unusually strong manifestation,” said Happy. “Try talking to her, JC. See if she’ll answer you.”

“What’s her name?” said JC. “Do we at least have a name for her?”

“Kim Sterling,” said Melody.

JC moved in close beside the ghost, and she turned her head slowly to look at him with her lost, dreamy eyes.

“Kim,” said JC. “Kim, what are you doing here?”

“I’m an actress,” she said, in a warm sweet contralto voice. “On my way to an audition. It’s a good part, come right out of the blue; and I have a good feeling about it. This could be my big break, at last. I could really shine, in a role like this. I wish the train would come. It feels like I’ve been standing here for ages.”

JC didn’t have the heart to tell her that the train would never come, for her. Kim smiled at him suddenly.

“Do I know you? You look nice. Kind.”

“I try to be,” said JC. “But it’s not always easy. I’m here to help.”

“That’s nice,” said Kim. “But I don’t need any help. I’m fine.” She looked directly at him, and some of the dreaminess went out of her eyes. “Except . . . I have this feeling, that there’s somewhere else I ought to be.”

“Yes,” said JC.

“I feel so cold . . . and alone . . .”

“You’re not alone any more,” said JC. “I’m here. We’re all here, to help you. I’m JC.”

“I’m Kim. I shouldn’t be here, should I?”

“No.”

“Why are you crying, JC?”

He hadn’t realised he was.

“Are those tears for me, JC? No-one ever shed a tear for me before. No-one ever cared that much. I’ve been so alone since I came to London, despite all the people . . . I wish I’d met you before, JC.”

“Yes,” he said. “I wish I’d met you before, Kim.”

She reached out a hand to him to wipe away the tears on his cheek. But her fingers were already transparent by the time they reached his face; and when he put up a hand to hold hers, his fingers passed right through her ghostly hand. Kim Sterling faded slowly away and was gone, and JC was left standing alone on the edge of the platform, reaching out to no-one. And then Kim reappeared, standing at the end of the platform, next to the tunnel-mouth from which the hell train had appeared. She looked entreatingly at JC, then faded away again. JC turned savagely to Happy and Melody.

“That’s it! She’s the key, the focal point, the start of this haunting! Solve her murder, and we solve this case.”

“Slow down, slow down,” said Melody. “We don’t know anything of the sort. Yes, her murder might be the instigating factor, but . . .”

“But nothing. Grab what you need; we’re going after her.”

“Are you sure about this, JC?” said Happy. “I could feel what you were feeling. And this is very definitely not the time to fall for a pretty face.”

JC glared at Happy. “Stay out of my head!”

“It’s not my fault! In my current, well-medicated state, it’s like you’re shouting the whole contents of your head at the top of your voice, and I do wish you wouldn’t.”

“She’s the key,” JC said stubbornly. “And we are going after her. Right now.”

“Going where?” said Melody.

“We follow her! She’s leading us somewhere.”

“I’m not leaving my machines here, unguarded!” said Melody. “Anything might happen to them!”

“Your machines can look after themselves; you’ve said so often enough,” said JC. “We have to go now; we can’t risk losing her!”

“It’ll all end in tears,” said Happy. But as usual, no-one was listening to him.

JC was already off and running down the platform, heading towards where he’d last seen the ghost. Happy and Melody looked at each other, shrugged pretty much in unison, and went chasing after JC and the ghost of Kim Sterling.

The three ghost finders ran full tilt through Oxford Circus Station, chasing the ghost as she receded endlessly before them, appearing and disappearing and reappearing. JC led the way, pursuing Kim down the endless white-tiled corridors, dashing in and out of low-arched entrances and exits, onto station platforms and off again; and still she hung on the air before him, drawing him on like some ghostly will-o’-the-wisp. Sometimes she was directly ahead of him, so close he could almost reach out and touch her, sometimes so far ahead she was only a pale figure in the distance. She wasn’t moving of her own accord. He knew that. He could see it in her face, and in her eyes. Sometimes she called out to him, but her voice only came to him as the barest whisper. Something was using her as bait, drawing him like a fish on a line. JC knew that, but he kept going anyway, running as fast and as hard as he could drive himself. Because this was his job, because he had to stop the haunting from spreading . . . and because he couldn’t, wouldn’t, let Kim down.