Logan settled behind his desk, cricked the plastic lid off his coffee, then unwrapped the bacon buttie. ‘He’s right: go home. You look like an extra from a zombie film.’ The squeezy bottle of tomato sauce was locked away in the bottom drawer, where the thieving sods on nightshift couldn’t get at it. Logan liberated it and slathered the bacon in scarlet.

‘Come on, McRae, I can’t do it myself: I’ve been up all night, the post mortem’s at half nine and there’s no way that’s going to be done before lunchtime. I need an experienced pair of eyes on the ground now, not this afternoon.’ Leith thumped a blue folder onto Logan’s in-tray. ‘I’ll owe you one.’

‘You already owe me one.’

‘Fine, so I’ll owe you two. Please? ’

Logan eased open the folder’s front flap. Photograph: a blackened bloated body specked with mould, lying on a stainless-steel cutting table. The skin was lined with tiny dark-purple cuts each one surrounded by darker circular mottling that might have been bruises. Difficult to tell with the remains being so decomposed. No hair on the head, groin, armpits, or chest. Same as their necklacing victim. Logan closed the folder again and took a bite of his buttie. Bacon crunched between his teeth, filling his head with its smoky salty tang. ‘What about Ding-Dong? ’

‘Detective Inspector Bell couldn’t find his arse with both hands if you duct-taped them to it. Come on.’

He licked a blob of sauce from the side of his mouth. ‘OK, but if Steel asks, I’m off doing something about the necklaced guy. Deal? ’

Leith stood. ‘Deal.’ Then made for the door.

As soon as it shut, Rennie crumpled into the seat again, arms hanging at his sides, head thrown back, showing off a stubbly Adam’s apple. ‘Urrrrrrrgh. . .’

‘I told you to go home.’

‘Why can’t everything be like it used to? ’

‘You’re making the place look untidy.’

‘No, seriously.’ He raised his arms, then let them flop down again. ‘Being detective sergeant’s a crap job. All the DIs and Steel treat you like crap, all the DCs and uniform whinge and bitch and give you crap about everything you ask them to do. It’s like . . . being the filling in a crap sandwich.’

Logan took Leith’s folder from the in-tray and pulled out the photos inside. ‘My heart bleeds.’

‘We used to be so happy. . .’

‘So resign. Tell Steel you don’t want to be a DS any more.’

A snort. ‘Yeah, good luck explaining that to the wife.’ He wrapped his arms around his head. ‘Why couldn’t it have been a simple one-punch murder, or a nice easy domestic? ’