He threaded his way through the carriage to stand by the next set of doors. Henson was staring into space; then she turned and studied her reflection in the dark window, and fished in her handbag for a square doublesided mirror. She licked her lips and threaded her fingers through the front of her hair and shook it out, then folded the mirror and zipped it back into her bag.

She was totally unaware of Oakhill watching her, strap-hanging only a few feet away.

Amson was leaning between the front seats with a map in his hand. “He’s here, could be heading for Euston or King’s Cross, but he’s ducking and diving . . .”

“Hold it, Control’s coming through.” She raised a hand to the earpiece on which she was picking up relayed messages. “He’s jumped on a number seventy-three bus. No, he’s off it, he’s turned in the direction of Battle Bridge Road, behind King’s Cross station . . .”

Amson pointed it out on the map. “That’s here. Doesn’t look like he’s going for a train, but there are lock-ups in the railway arches all along here . . .”

“Come on, you bugger, go for the car, get your bloody car!”

A voice said in her ear, “You’re out of luck, car five-four-seven. Your man’s just gone into a café, he’s sitting talking to the owner. It’s the taxi stopover . . .”

Tennison pursed her lips and tapped her foot regularly against the transmission tunnel of the car. Her ear was aching because she was so uptight at the possibility of missing a radio call that she kept pressing the earpiece harder into her ear.

“What the fuck d’you think he’s doing?”

Amson shrugged. “Could do with a cup of coffee myself.” His fingers drummed against the back of her seat. He was shrugging it off, but like everyone else he was right on the edge, waiting, waiting . . .

Among the crowded little stalls selling jeans and T-shirts, DC Jones found a tiny booth containing only a small white-covered table and two chairs. A sign nailed to the top of the wooden frame announced: “Noo-Nails by Experienced and Qualified Beautician.”

Annette Frisby, the proprietress, was bending over a client’s hand, carefully painting her new nails a violent pink. Jones squashed himself in beside them and showed Annette his identification and a photograph of Karen Howard.

“Have you ever done this girl’s nails?”

She squinted at the photo. “I couldn’t tell you, I do as many as eight a day . . .”

“Look at her again.” He tried to squat down to her level and pointed at the beautiful young face. “She was found murdered, on the fourteenth of January last. Look again, did she ever come to this stall?”

“January? I wouldn’t have been here anyway. My friend takes over when I can’t do it.”

Jones ground his teeth in frustration. “Have you got her name and address?”