The boy had the pale white skin and the skinny physique of his mother. But the dark hair, the heavy dark eyebrows, and above all those bitter chocolate eyes gave a hint of something else. What she had always suspected. As she drove away she knew she would have the answer to her question within a few days.

Twickenham police station in West London was a traditional English nick, even down to the prominent blue Victorian lamp outside. Inside, though much modernised, it had rather too many separate offices for the twenty-first century’s more collegiate type of policing. Harshil Roy, scion of the Empire of Spice dynasty, was half an hour late for his interview. Gillard passed the time squinting at the company’s annual report on his phone, while DI Claire Mulholland caught up on some of the paperwork for the pub fight case.

When the businessman did turn up, neatly dressed in a dark suit and full of apologies, they took him to the rape interview suite which had the kind of soft seating, pot plants and comforts designed to put witnesses at their ease. He looked exhausted, his face drawn, and as soon as he sat down, he rested his head on the back of the sofa, closed his eyes and exhaled heavily.

‘Tough day, I expect,’ Gillard said.

He nodded, his eyes still closed. ‘I’ve had to shoulder my mother’s work burden as well as my own, though I can hardly concentrate.’ He only opened his eyes when his phone chirruped, picking it up to look at the message.

‘Auditors.’ He made it sound like a curse, then looked up at Gillard. ‘Our year-end is due soon. This couldn’t have happened at a worse time.’

Gillard introduced Claire, and then asked that the interviewee turn off and put away his phone, which had sounded constantly.

‘Have you found the cyclist?’ Harry asked. ‘The papers said—’

Gillard held up his hand. ‘If we try to cover every piece of speculation in the newspapers we’ll never get out of here. And no, we don’t yet know who the cyclist was.’

‘Was it a really a mugging? Or do you think they had an argument? Have you found her purse?’

The triviality of most killing adds cruelty to bereavement: knocking into the wrong person on the commuter train, the drunken friends arguing over a football score, addicts squabbling over the last syringe-full, and here, quite possibly, an argument between strangers in a snowy park. Gillard could see the excruciating bafflement in Harry’s big brown eyes. ‘We simply don’t know. Now, Mr Roy, we will make this as brief as possible,’ Gillard said.

‘Please, call me Harry. Everybody does.’ He managed a wobbly smile.

They quickly went through his movements, which included arrival at Heathrow on a flight from Mumbai only a few minutes before his mother was killed. Everything checked out with the details they had already looked at. There was no doubt he was on the flight.

‘So what were you doing in India?’ Claire asked.