Crippen the dog was on the opposite side of the carriage, snuffling around the shoes of an irritated businessman. Strangeways had smuggled the Jack Russell into the station inside his jacket, but Vince had insisted on him standing some distance away, further along the platform. There was a closed circuit monitoring system placed near the tunnel entrances, and even though he was unsure of the technical capabilities of such equipment, he had begun to suspect that the members of the League were somehow utilising the traffic cameras, so why not the ones in there? Some of the new trains had cameras in their carriages, but this was ancient Northern Line rolling stock, unfitted with modern technology. He was pretty sure they were safe for the time being.

'So, do you do this a lot? Charging around town on treasure hunts?'

'It passes the time,' Vince replied. 'What do you do apart from wander the streets with a dog on a piece of string?' He waved his hand at the terrier, which had its head in a dozing woman's shopping basket. 'And why does it always have to be string? What statement are you trying to make?'

'The statement that I haven't got any money,' Strangeways said and shrugged. 'I would have thought that was fucking obvious.'

'Are you unambitious?'

'No,' he protested. 'I have ambitions. They just haven't been realised.'

'Why, what do you want to be?'

'Ideally, a shepherd. Actually, I could have got myself a graphics degree if I'd had the application.'

'Applying yourself is a matter of -'

'No, man, the form, I didn't get the application form posted in time. I have immense artistic ability. What I don't have is a job and somewhere to live.'

'Why can't you get a job?'

'Are you kidding? There's no call for illustrators any more. Everything's comped together on Macs. I'm a fine artist. I don't want to cobble adverts together. That's for the computer generation, cheap labour that does what it's told and to hell with artistry.'

'There must be some -' Crippen caught his eye. 'Your dog.' The Jack Russell had partially eaten a bar of soap and appeared to be frothing at the mouth.

'I don't know why he does that,' said Strangeways, hauling the dog towards him and removing shreds of soapy paper from his canescent jaws. 'People think he's got rabies. I wouldn't mind having a go at club flyers, CD art an' stuff, but the competition's too far ahead of me now. Listen, why are you doing this? It's some kind of initiation test, is it?'

'Yeah, sort of. I'm doing it because I have to.' Perhaps it would be better to confide in him. Now, before they reached the next station. Deciding that communication was power, Vince attempted to outline his role in the evening's events. Between Chalk Farm and Golders Green stations he described how he had come to be involved with such a group as the League of Prometheus. Telling a stranger eased the weight of the problem. Strangeways thought about it, scratching at his skinny goatee. He carefully realigned the folds of his overcoat and sat back. 'Do you always do what people tell you to do?'

'This is different, believe me.' As they exited the station, Strangeways pondered the problem.

'Run this by me again. Perhaps I'm being thick. Some nights I've got less brain cells than a footballer's wedding, know what I mean? What are these people going to do if you don't follow their instructions?'

'I don't know. Maybe nothing. They might just be trying to scare me, but I don't want to take that risk.'

'So they're not going to – like, kill anyone, then.'

'Erm, well, yes they are, if they're not obeyed.'

'Don't you want to know how I knew about Speedwell? I mean, that's like a one in a thousand chance, you asking me.'

'Go on, then.'

'It's something all the older BT engineers know about. I trained as a telephone engineer for a while, but the work was so fucking boring. Just another branch of digital technology. I went back to the street. I've tried my hand at most things, but I always seem to be in the wrong place at the wrong time. I should have been training to use Photoshop on a graphics computer, and now I can't afford to. Doesn't that sort of thing ever happen to you?'

Vince smiled. 'All the bloody time. Why do you live on the street?'

'Why not? There's no rhyme or reason to the world any more. Nothing is safe. Nothing is sure except that the rich will put out your ambitions by pissing on the fuse. Fuck'em. Why not live according to the demands of each day?'

'Because if everyone did that society would collapse.'

'Stone me, you think it isn't doing that already? Look around you. We're living in the remnants of the past, like scavengers. All of us. A hundred years ago, that train we were just sitting on ran more efficiently than it does now. If we keep progressing at this rate, we'll soon be back in the Stone Age. People sometimes call me a tramp, but I'm not a tramp, I'm just homeless. The street is my office. I'm on the phone, look.' He pulled a mobile phone from his overcoat pocket and waved it at him. 'That's really all I need to conduct business.'

'Business?'

'A little buying and selling.'

'Oh, right.' Vince threw him a dubious look, deciding not to ask for details. 'Is it charged up?'

'Sure.'

'Can I use it?' Vince thanked him and punched in Louie's number. Inspired by Strangeways's rebellious attitude, he had decided to dispense with the League's rule forbidding telephone contact. Louie's answering machine picked up the call. Damn.

'There's the Seven-Eleven.' Strangeways pointed over the rainswept road.

ACROSS THE city, teenagers hung around outside Seven-Elevens in a state of expectant stasis, as if waiting to receive news of world-changing events, but the most that ever happened was a small exchange of drugs and money, a scuffle when the pubs turned out. Vince squeezed between two ominous youths sheltering beneath the awning and walked to the rear of the store. Strangeways remained outside with the dog. Crippen had been hawking up chunks of Imperial Leather ever since they left the tube station.

He found it easily enough, a small rectangular envelope sealed inside a misted plastic Jiffy-bag, taped behind the heavy plastic strips of the drinks cabinet. It made a thwuuuup noise as he removed it, and he was aware of the Chinese clerk behind the counter watching him in the convex mirror above the magazine racks. He purchased a suspicion-killing carton of orange juice and some nutrition-packed pepperoni sticks.

'So what's in it?' Strangeways tried to snatch the envelope from him as he emerged from the store.

'Move away from me, someone will see you.'

'There's no one around but kids, for God's sake. You're paranoid.'

'With good reason.' He pointed up at the traffic cameras on the corners of the buildings. 'Do you know who's watching? I don't.'

'Open the damned envelope.'

'Let's get off the main street.'

They turned left and walked into a quiet side road filled with pebble-dashed bay-fronted houses, stopping beneath the spattering aureole of a streetlamp. Vince tore the envelope from its plastic cover and ripped open its flap. Inside was the usual single page of chemically-treated vellum. He unfolded it and stared with a puzzled frown. At the top was the stated time allowance of an hour, and the title of the challenge:

The Challenge Of An Exotic Childhood

'Yeah, and? Well, what else does it say?'

'Nothing.'

'What do you mean, nothing?'

'See for yourself.' He passed the page to Strangeways. The rest of it was blank but for a large round blot of ink in the centre.