Dr Goulding huffed a breath onto his little rectangular glasses, polished them on a cloth, then slipped them back onto his long, hooked nose. Ran a hand through the thick black hair on top of his head, cut short like animal pelt, grey flecks spreading their way around his temples. A pair of flaming dice sat in the middle of his bottle-green tie. He reached out and pressed play on the video console. ‘This is the interesting bit.’

Logan scooted his chair closer as the crackling screen filled with the interior of interview room two. Robbie Whyte was sitting in the dead seat – the one bolted to the floor – Goulding in the one opposite him, the legs and stomach of PC Guthrie just poking into the side of the frame.

Whyte gave his lopsided shrug again. ‘I don’t know. I found it.’

The on-screen Goulding nodded. ‘You found a dog’s head.’ Not a question, just a statement.

‘I know she still loves me. . .’

‘Sometimes, Robbie, it’s hard for us to accept that the huge feelings we have aren’t shared by others.’

‘No: she loves me. I know she does.’ He sat back in his seat and stared up at the camera. ‘There was this summer we got a caravan in Lossiemouth. Was a friend’s dad’s and we stayed there for a whole fortnight. Just her and me and Wee Robbie. Caught fish and cooked them under the stars and smoked so much weed one night we saw a kelpie. . .’

‘I see. You named the dog, “Wee Robbie”. Was that your idea, or Nichole’s? ’

‘Going to get married and have kids. Boy and a girl. Always wanted a son, you know? Someone to be a chip off his old man’s block.’

A nutjob who’d cut the head off his own dog. Yeah, that was something to aspire to.

The real-life Goulding pressed pause. ‘So when she left, she not only rejected him, she rejected his future child as well. A double blow. Then, when his mother died, that was the final straw. He couldn’t cope any more.’

‘He gave the dog the same name he was going to give his kid? ’

‘You asked if Robert Whyte would be capable of murder. . .’

Silence.

Logan poked Goulding in the shoulder. ‘Well? ’

‘In killing the dog – the emotional surrogate for an unborn son and his potential future with the woman he loves – Robert’s metaphorically killing himself and everything he’s hoped for over the last eight or nine years. He’s a dead man. You can’t hurt the dead.’

‘Could he necklace someone? Or torture them to death? ’