‘When was the last time you saw Ms Lockhart?’

‘Some time last July.’ July 23, around half past ten. ‘Did she dump you?’ Again, the sudden lurch into high-school crudeness. Nick flinched, but Seth was quick off the mark.

‘Would you like to rephrase that question, Detective?’ Royce adjusted his tie. ‘Did your relationship end acrimoniously.’

‘No.’

There had been a lot of fights with Gillian. Sometimes he thought she provoked them deliberately, because she couldn’t resist the drama. She’d threaten to leave him, and he’d be up until four in the morning begging her to reconsider. Other times it just seemed to be the inevitable eruption of two tectonic plates colliding or moving apart – those were the ones that could last days. It kept him on a knife-edge.

But there’d been no fight the night she left him. She’d cooked him dinner, teased him about his new haircut and gone to bed with him. She’d been subdued all evening, which was unusual but not unheard of. The next morning he woke alone to find a note on the pillow.

It’s over. x G

No apologies, no explanation, no tears, no way back. A one-night stand that lasted six months.

‘Did you try to contact her again?’ Royce asked.

Nick shifted uncomfortably in his seat. ‘A few times.’

Those were memories he didn’t want to relive: dark days of phones that rang and were never answered; emails written, re-drafted and abandoned; meals forgotten; work ignored so long that even Bret started to worry.

‘So – just so we can be clear – when exactly was the last time you communicated with Ms Lockhart?’

‘Last July. Then nothing until I got the video call from her three days ago.’

‘So you weren’t aware that she had moved to Paris and got a job with an auctioneers?’

‘I learned that after I got the message.’

‘Even though you’d shown no interest in finding it out for the previous six months?’

‘I was worried. I told you what I saw on the computer.’ Royce leaned closer. ‘And did you then call Ms Lockhart from your cellphone about an hour before Bret Deangelo was murdered?’

The room seemed closer, the lights too bright. ‘I got the number of her office in Paris and called it.’

‘Paris is six hours ahead of East Coast time. Did you really expect she’d be there?’

‘The auction house told me there was a late-night sale going on. I thought it’d be worth a try. You can check that with Stevens Mathison, if you like,’ he added. Too defensively, judging by the look Seth gave him.

Royce powered on. ‘Was it?’

‘What?’

‘Worth a try.’

‘She wasn’t there, if that’s what you mean.’

‘But you spoke to someone? Someone who’ll confirm your story.’

‘I don’t remember his name. I – I don’t think he gave it. He sounded English.’

‘We’ll look into it.’ Royce dismissed it and moved on. ‘Now, when Ms Lockhart contacted you via email-’

‘It was Buzz,’ Nick interrupted. ‘Right. The same thing you used for snooping on your room-mate.’

Seth raised his pen, a silent objection.

‘OK, she Buzzed you – have I got that right?’

Nick nodded.

‘Did she send anything with her message?’

He was trying to be casual, but Royce couldn’t really manage low key. He knows, Nick thought. Did I tell him? He didn’t think so. They must have looked on the computer they’d taken.

There was no point stalling. ‘She sent me a file – a picture of a medieval playing card.’ He saw the next question coming and cut it off. ‘I have absolutely no idea why. I wish I knew.’

Something in the hopelessness of his voice seemed to check Royce’s momentum. Seth took advantage.

‘My client’s been very cooperative in answering all your questions. Would you mind informing him why you’re so interested in his former partner?’

Royce stood. ‘I think, Mr Goldberg, you and I should have a moment alone.’ He held the door open and gestured Nick to go out. ‘We’ll just be a minute.’

In fact they were ten. Nick watched them through the window in the door, the wires of the safety glass like prison bars. He could see both men standing, facing each other across the table and arguing intently. When they were finished, it wasn’t Seth who came out but Royce.

‘Your lawyer wants you.’ He smirked. ‘I’ll be by the coffee machine.’

Nick went back in the room. The video camera had been turned off. Seth gave a weary sigh.

‘They want you to surrender your passport. They think you might be a flight risk. They seem really hung up about this call you made to Paris just before Bret was killed.’

‘Do they think I hired some French guy to kill him?’

‘Keep your voice down.’ Seth glanced at the windows. ‘Rule number one: never use sarcasm to the police. Same goes for irony. That stuff is filet mignon to prosecutors – they slice it up, serve it to the jury any which way. This whole thing is a mess. You should’ve talked to me before you told them anything, especially that story about the assassin on the roof. Did you expect them to believe that?’

‘It’s the truth,’ Nick protested.

‘That’s not what I said. Royce is convinced you’re either half-crazy or guilty as hell. The only thing keeping you out of jail is the testimony of an eight-year-old kid. Bret’s not an easy case for the defence. And they’ve got something on Gillian too.’

‘What?’ Nick felt dizzy. Had the police cracked the picture? What else did they have?

‘I’ve done the best I can for you,’ Seth was saying. ‘Royce was ready to arrest you right there. I convinced him to go easy for the moment. This passport thing’s his compromise.’

‘It’s at the apartment. Will they let me in there?’

‘I’ll come with you.’

XXII

Paris, 1433

Tristan’s house was an enormous hôtel: a square stone-built mansion near the church of St Germain. It could have been anywhere. The moment you passed its gate the city was relegated to a distant smudge of smoke and spires behind the wall. Tristan’s father had a role at the court of King Charles, from where he had been dispatched on some diplomatic errand to Constantinople. He had been gone some months and would be away for many more. He had taken his wife, his two daughters and most of his household, leaving Tristan with an almost-empty house and stern instructions to behave himself.

If Tristan’s father feared that his son might consort with prostitutes, idlers and gamblers then he had every reason to worry. If the secret of the Stone could have been discovered through fornication, or won at cards, Tristan would have had it within a month. But the whores and drinking and gambling were merely diversions from his true aim. With three older brothers and two sisters who would soon need dowries, he knew his days of living in the grand house – all he had ever known – were drawing to their end. The knowledge seemed to tear him apart, pitting the two halves of his soul in war against each other. He squandered his inheritance ever more savagely in couplings and wagers whose only pleasure was defiance, but he also pursued the Art with the obsessive conviction that it would free him from his father’s legacy.

Tristan had made his laboratory in a tower that had been added to the east wing some years earlier. The first time he brought me there it took my breath away. With the sort of architectural absent-mindedness that only the nobility can afford, the inside of the tower had never been finished: you could stand on the ground and stare all the way up to the coned roof, so high it seemed to funnel into eternity. Broad windows for chambers that were never built pierced the stone walls above, while at our level the whole surround was painted with perfect copies of Flamel’s panels in St Innocent’s. Only a brick furnace set into the far wall, and the door opposite, broke its sweep.

Tristan pointed up into the giddy darkness. ‘Truly a place to dream of grasping the secrets of heaven.’