‘Keep them. Never know when you might feel the need.’ He got to his feet. The blood was beating in his skull now, despite the paracetamol. That’s the way Flip is: Costello had spoken of her in the present tense – a casual remark, or something more calculated? Costello stood up too, now, and he was smiling, though without much humour.

‘You never did answer that question, did you?’ he said.

‘I’m keeping an open mind, Mr Costello.’

‘Are you now?’ Costello slipped his hands into his pockets. ‘Will I see you at the press conference?’

‘Could be.’

‘And will you be on the lookout for slips of the tongue? Something like your forensic bods?’ Costello’s eyes narrowed. ‘I may be the only suspect, but I’m not stupid.’

‘Then you’ll appreciate we’re on the same side … unless you know differently?’

‘Why did you come here tonight? You’re not on duty, are you?’

Rebus took a step closer. ‘Know what they used to think, Mr Costello? They thought murder victims kept an imprint of their killer on their eyeballs – last thing they ever saw. Some killers, they gouged out the eyes after death.’

‘But we’re not so naïve these days, Inspector, are we? You can’t hope to know someone, to get the measure of them, just from eye contact.’ Costello leaned in towards Rebus, his eyes widening slightly. ‘Take a good long look, because the exhibit’s about to close.’

Rebus met the gaze, returned it. Costello was the first to blink, breaking the spell. Then he turned away and told Rebus to leave. As Rebus made for the door, Costello called out to him. He was wiping the cigarette packet with a handkerchief. He did the same with the lighter, then tossed both items towards Rebus. They fell at his feet.

‘I think your need’s probably greater than mine.’

Rebus stooped to pick them up. ‘Why the handkerchief?’

‘Can’t be too careful,’ Costello said. ‘Evidence can turn up in the strangest places.’

Rebus straightened, decided against saying anything. At the door, Costello called out goodnight to him. Rebus was halfway down the stairwell before he returned the sentiment. He was thinking about the way Costello had wiped both lighter and packet. All the years he’d been on the force, he’d never seen a suspect do anything like that. It had meant Costello was expecting to be set up.

Or, perhaps, that was what it was intended to look like. But it had shown Rebus a side of the young man that was cool and calculating. It showed someone who was capable of thinking ahead …

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