‘Sorry,’ Ava said, pulling her crime-scene suit hood up immediately. ‘I was just hoping against hope that the two deaths had nothing to do with one another.’

‘Bursting your bubble there,’ Ailsa said. ‘High levels of psychological torture involved in both. They’d each have known what was coming. This man would have died substantially faster. He’d have been rendered unconscious as soon as the electricity went through him, but still, that’s no way to go.’

Callanach finished his conversation with some other fire officers and joined them.

‘Fuck …’ he muttered.

Ailsa gave him one of her looks reserved for particularly bad language, which she discouraged at her crime scenes.

‘Ah, yes!’ she said. ‘Men always react badly to the disfigurement of male genitalia. This one is especially shocking, I’ll give you that.’ She stood up and leaned over the corpse. ‘So our victim is, I believe, Japanese by race, between twenty-five and thirty years of age at first assessment – visual only – and I’d estimate five foot ten tall. His clothing was unbuttoned and unzipped to allow for exposure of his genitalia and chest.

‘There’s a jug thrown onto the sofa, which we’ll take for fingerprinting once it’s been photographed in situ, but my guess is that it was used to pour water over the body to maximise electrical conductivity. What’s left of this man’s penis’ – she took an implement from her bag and hooked it under the blackened inches of flesh – ‘was originally inserted into the toaster before the current was switched to live. With the water, it was easily enough to have killed him. The burns are in line with death by electrocution, as is the splitting of the skin up the groin. His legs were trapped between items of furniture to prevent him from jerking away from the toaster. The other burn points on the body aren’t separate injuries, just a side effect of the electricity trying to leave his body.’

Callanach walked to the door of the flat, and inspected the locks and surfaces.

‘No damage,’ he said. ‘Just like at Fenella Hawksmith’s place. Whoever did this was let in without a fight.’

One of the tech officers handed Ailsa a passport.

‘Here we go. Looks like the victim is Osaki Shozo, twenty-six years of age. He’s wearing a wedding ring and I noticed two pairs of women’s shoes in the corner. We’ll need his wife to attend the mortuary to formally identify the body.’

‘I’ll get straight on it,’ Ava said.

‘You’d better,’ Ailsa said. ‘Whoever killed Mr Shozo here is terribly disturbed. This, and what happened to Fenella Hawksmith, is the work of a deeply psychotic mind.’

‘The deaths are close together,’ Callanach noted. ‘Usually there’s a longer recovery or planning period, or at least a greater time span when the offender’s feeding off reliving the event.’