Lynley showed his ID to one of the constables, who signaled to the others to move the roadblock long enough for the Bentley to pass. Before he did so, Lynley said to the man, “Don’t let anyone other than SOCO inside. Anyone. I don’t care who they are or what they tell you. No one passes who isn’t police with proper police ID.”

The constable nodded. The flash of camera lights told Lynley that the press was already hot on the story.

The first stretch of Wood Lane comprised housing: an amalgamation of nineteenth- and twentieth-century buildings that consisted of conversions, apartments, and single homes. Perhaps two hundred yards along, however, the buildings stopped abruptly and on either side of the street the woods spread out, completely unfenced, utterly accessible, looking in this weather both brooding and dangerous.

“Good choice,” Havers muttered as she and Lynley alighted from the car. “He has a way, hasn’t he? You’ve got to give him that.” She turned up the collar of her donkey jacket against the rain. “Like a set from a thriller film, this is.”

Lynley didn’t disagree. In the summer, the area was probably a paradise, a natural oasis that afforded an escape from the prison of concrete, stone, brick, and tarmac that had long ago enveloped the rest of the native environment. But in the winter, it was a melancholy spot in which everything was in the process of decay. Layers of decomposing leaves covered the ground and sent forth the odour of peat. Beeches toppled by storms over the years lay in various stages of rot right where they had fallen, while branches severed from trees by the wind punctuated the slope, growing moss and lichen.

Activity centred on the south side of Wood Lane, where the park dipped down towards the allotments and then up again towards Priory Gardens, which was the street beyond them. A large square of translucent plastic suspended from poles formed a rough shelter for an area perhaps fifty yards to the west of the allotments. There, an enormous beech had been torn from the ground more recently than the others, for where its roots had been there was still a hollow that time, earth, wind, small creatures, ferns, and bracken had not yet filled in.

The killer had placed the body in this hollow. At the moment, a forensic pathologist was attending it while a SOCO team worked with silent efficiency in the immediate area. Beneath a tall beech some thirty yards away, an adolescent boy was watching the activity, one trainer-shod foot up on the trunk behind him to prop him up and a rucksack at his feet. A ginger-haired man in a trench coat stood with him, and he jerked his head at Lynley and Havers in a signal to come over and join him.

Ginger Hair introduced himself as DI Widdison from the Archway police station. His companion, he said, was Ruff.

“Ruff?” Lynley glanced at the boy, who glowered at him from beneath the hood of a sweatshirt that was covered by an outsize anorak.

“No surname at present.” Widdison walked five paces away from the boy and took Lynley and Havers with him. “Found the body,” he said. “He’s a tough little bugger, but it’s shaken him up. Sicked up on his way to get help.”

“Where did he go for that?” Lynley asked.

Widdison tossed a nonexistent ball back in the direction of Wood Lane. “Walden Lodge. Eight or ten flats in there. He leaned on the bells till someone let him inside to use the phone.”

“What was he doing here, anyway?” Havers asked.

“Tagging,” Widdison told her. “Course, he doesn’t want us to know that, but he was shaken up and gave us his tag by mistake, which is why he doesn’t want to give us his real name now. We’ve been trying to catch him for some eight months. He’s put ‘Ruff’ on every available surface round here: signs, dustbins, trees. Silver.”

“Silver?”

“His tagging colour. Silver. He’s got the cans of paint in that rucksack of his. Didn’t have the presence of mind to chuck them before he phoned us.”

Lynley said, “What’s he given you?”

“Sod all. You can talk to him if you’d like, but I don’t think he saw a thing. I don’t think there was anything to see.” He tilted his head in the direction of the intense circle of work surrounding the body. “I’ll be over there when you’re ready.” He strode off.

Lynley and Havers returned to the boy, Havers digging into her bag. Lynley said to her, “I expect he’s right, Barbara. I don’t imagine taking notes-”

“Not going for the notes, sir,” she replied, and she offered the boy her crumpled packet of Players when they joined him.

Ruff looked from the cigarettes to her, back to the cigarettes. He finally mumbled, “Cheers,” and took one, which she lit for him with a plastic lighter.

“Anyone about when you found the body?” Lynley asked the boy once he’d had time to suck hungrily on the cigarette. His fingers were dirty, with grime crusted beneath the nails and the cuticles. His face was spotty but otherwise pale.

Ruff shook his head. “Someone in the ’lotments, is all,” he said. “Old bloke turning the earth with a shovel like he’s looking for something. I seen him when I come down through Priory Gardens. On the path. Tha’s all, innit.”

“Were you by yourself tagging?” Lynley asked.

The boy’s eyes flashed. “Hey, I di’n’t say-”

“Sorry. Did you come into the park by yourself?”

“Yeah.”

“See anything unusual? A car or van that didn’t look right, up on Wood Lane? Perhaps when you went to phone for help?”

“I di’n’t see fuck,” Ruff said. “Anyways, there’s lots ’f cars parked up there all the time in daytime. Cos people come into town from outside and they take the tube rest of the way, don’t they? Cos tube’s just over there. Highgate station. Look, I tol’ the dibble all this. They ack like I did summat. An’ they won’t let me go.”

“That might have something to do with your not giving them your name,” Havers told the boy. “If they want to talk to you again, they won’t know where to find you.”

Ruff looked at her suspiciously, a bloke trying to suss out a trick from among her words. She said reassuringly, “We’re from Scotland Yard. We’re not going to drag you to the nick for spraying your name about. We’ve bigger fish to fry.”

He sniffed, wiped his nose on the back of his hand, and relented. He was called Elliott Augustus Greenberry, he finally admitted, eyeing them sharply, as if watching for incredulous expressions to cross their faces. “Double ell, double tee, double ee, double ar. An’ don’ tell me how fuckin stupid, it is. I know, don’ I. Look, c’n I go now?”

“In a moment,” Lynley said. “Did you recognise the boy?”

Ruff brushed a greasy lock of hair off his face, tucking it into the hood of the sweatshirt. “Wha,’ him, you mean? The…it?”

“The dead boy, yes,” Lynley said. “Do you know him?”

“I never,” Ruff said. “Nobody I ever seen. Could be he’s from round here somewheres, like up on the street over there behind the ’lotments, but I don’t know him. Like I said, I don’t know fuck. C’n I go?”

“Once we have your address,” Havers said.

“Why?”

“Because we’ll want you to sign a statement eventually, and we need to know where to find you, don’t we.”

“But I said I di’n’t-”

“It’s routine, Elliott,” Lynley said.

The boy scowled but cooperated, and they released him. He shed the anorak, handed it over, and took off down the slope, west towards the path that would lead him up again to Priory Gardens.

“Anything from him?” DI Widdison said when Lynley and Havers joined him.

“Nothing,” Lynley said, handing over the anorak, which Widdison passed to a sodden constable, who donned it gratefully. “Aman digging in the allotments.”

“That’s what he told me as well,” Widdison said. “We’ve got a door-to-door going on up there now.”

“And along Wood Lane?”

“The same. I’m reckoning our best bet is Walden Lodge.” Once again, Widdison indicated a modern and solid-looking block of flats that squatted at the edge of the woods. It was the last building on Wood Lane before the park, and on every side it presented balconies. Most of them were empty save for the occasional barbecue and garden furniture covered for the winter, but on four of them, watchers stood. One of them held up binoculars. “I can’t think the killer brought the body down here without a torch,” Widdison said. “Someone up there might have seen that.”