“There’s no need to pull the homeless-puppy routine with me, Arthur; it doesn’t wash anymore. I don’t mind coming with you. If Banbury’s going to be pulling up floorboards and relaying server cables I wouldn’t want to be here anyway. Besides, you’re not allowed to drive alone on motorways since that business with the travelling circus.” Seven years earlier, Bryant had accidentally rear-ended a Chessington Zoo truck and released a startled lion into the slow lane of the M2. “When are you planning to leave?”

“First thing in the morning.” Bryant dragged out a much-folded map and pinned it on the crowded wall behind him. “I’ve already plotted our route, although this ordnance survey map was published before the war, so it may contain inaccuracies.”

“Good God, it won’t have motorways marked if it was published in the forties.”

“I meant before the Great War. 1907, actually.”

“That’s no good,” said May, “I’ll print something from the Internet.”

“No, you won’t, the system’s down.” Dan Banbury sauntered in, eating an iced bun. He always seemed to be eating or drinking. “Raymond told me the unit would be empty this week.”

“He didn’t think to warn any of us,” Bryant complained. “Anyone else here?”

“Full complement,” said Dan through a mouthful of sugared dough. “They’re milling around in the hall, waiting to be told what to do.”

DC Colin Bimsley came from a long line of spatially challenged law enforcers. Like his father and grandfather before him, it was enthusiasm rather than expertise that kept him in the field. Despite perforated eardrums, flat feet and an inner ear imbalance that found him periodically lying on his back, he was determined to bring honour to his family. On the plus side he had a heart of oak, being humane, decent and fair-minded, as strong as concrete and, barring the effects of an occasional self-inflicted head wound, quick to react. True, his brain sometimes lagged a little behind his body and his hand-eye coordination was virtually nonexistent, but to any woman who valued fidelity and reliability over smart-arse remarks, he was a godsend.

All of which made it even more unfathomable that DC Meera Mangeshkar could remain so stubbornly resistant to his charms. His compliments were greeted with sarcasm, and his attempts to lure her out for a drink were met with unforgiving dismissal. The diminutive Indian officer was ambitious and determined, hard in mind and body, and following a career path as preordained as a logic board. Bimsley’s shambling heroism impressed her no more than his offers to take her down Brick Lane for a curry with his mates. But they were shackled together now, sharing an office at the unit, and there was no alternative but to make the best of things. John May had planned it this way; he drew the best from staff by placing them in the proximity of opposites.

Wary of her threat to stick him with a harassment charge, Colin Bimsley entered the office quietly and began leafing through the week’s activity folders. Meera raised her head from her paperwork, regarding him suspiciously. “What?” she asked finally.

“I didn’t say anything.” Bimsley looked startled. His fellow DC rarely instigated any conversation.

“Exactly; you’re being too quiet. You’re up to something.”

“I can’t win with you, can I?” He sighed. “If I speak, you always tell me to shut up.”

“Yeah, well, I don’t trust you.”

“You don’t trust anyone, Meera.” He knew she had spent time on some of the capital’s poorest estates, in Peckham, Dagenham, Deptford, and Kilburn. It would be hard not to become cynical after a daily diet of gunshot wounds and stabbings committed in chip shops and at bus stops, where drug feuds were as liable to be settled at family weddings and christenings as on the street. Even so, there were days when she seemed barely able to contain her anger. “But if you did decide to trust someone,” he said, “you could tell me anything.”

“Thanks, Colin, but if it’s all the same to you I’d prefer to eat my own colon first.” Her head lowered almost to the page as she returned to studying witness statements.

Be as nasty as you like, he thought. My back is broad. And I’ll persevere until the day I find out what makes you tick.

Next door, April rose from her dead computer screen and walked to the window of her office. The sky was animated with roiling clouds, dark and volatile, filled with glimpses of amber and emerald. The streets around the tube station were almost deserted. Camden was one of the most crowded, dangerous and interesting boroughs in London; the rush hour lasted around the clock and the pavements were never free of life, but there was something different about today. Raymond Land had come around telling everyone they were on paid leave for a week, but she could not trust herself to go home. Having conquered her agoraphobia with her grandfather’s help, she was loath to allow it the opportunity of returning within the confines of her safe, small flat.

“Are you okay?” John May stuck his head around the door. “May I come in?”

“Of course.” April still felt like an interloper at the unit, despite her involvement in an investigation that had finally closed a decades-old cold case. She knew there had been suggestions of nepotism, that she had only secured the job because she was the granddaughter of the unit’s cofounder, but she was already winning the trust of her colleagues, and the work was fascinating.

In the filing cabinets opposite were secret details of cases no other unit in the country had the ability to unravel. The PCU had earned the right to handle the kind of investigations no-one in the Metropolitan Police force had the faintest interest in solving. They had captured demons and devils, phantoms and monsters; not real ones, of course, mostly deluded loners who believed themselves invulnerable to the law. Individuals who had stolen, blackmailed and killed for tenebrous, private purposes, to protect themselves, to hide truths, to destroy enemies. Murder, Arthur Bryant insisted, was invariably a squalid, sad business driven by poverty and desperation, yet the cases passed to the Peculiar Crimes Unit had often been marked by paradox and absurdity. Sometimes they were the dream cases other detectives fantasised about resolving, but Bryant and May chose their staff with care, employing novices who were knowledgeable social misfits, in the same way that computer companies sometimes hired the very hackers who had attacked their clients from behind bedroom doors.

“Arthur and I are taking a trip to Devon. You can come with us if you want. There’s plenty of room.”

“No, I’m still settling in here.”

“Will you be all right on your own?”

“I’ll be fine, I promise.” She gave him a reassuring smile. T have a lot of reading to catch up on. Someone needs to hold the fort. I’m working my way through Uncle Arthur’s journals.“

“Don’t believe everything you read in them,” May warned. “He has a habit of greatly exaggerating our successes.”

“And libelling everyone else. One police chief is described as ”a human leech with a mind genetically resembling old Stilton.“ I can’t imagine these accounts will ever see the light of day.”

“For God’s sake don’t tell him that. He thinks he has a bestseller on his hands. Remember to call me if you feel the slightest anxiety, won’t you?” He hovered awkwardly in the doorway. “I know I haven’t always been there for you in the past, but now that you know part of the reason why-‘

“It’s fine, Granddad,” April assured him. “You don’t have to say anything.”

But after her grandfather had left the office, his turn of phrase began to puzzle her. Part of the reason? He had finally been honest about her mother’s death, but was there more she had not yet learned about her blighted family?