James fetched a tea towel soaked in cold water and Stevens held it against the bruise on Hannigan’s forehead. As he did so, the man’s neck muscles twitched involuntarily.

‘So, what do you think?’ the DS said. ‘Was this an accident?’

‘That’s my guess,’ James said. ‘The external doors were locked from the inside and I haven’t noticed any open windows. Plus, it looks like the guy has been snorting cocaine while working his way through a bottle of JD.’

‘That would sure as hell have made the plonker unsteady on his feet,’ Stevens said. ‘Probably went upstairs and lost his footing.’

James nodded. ‘We won’t know for certain until he regains consciousness.’

‘Let’s hope he does. Just because he’s breathing it doesn’t mean he hasn’t fucked up his brain.’

The wail of a siren came from outside on the street and James went to the door to see an ambulance stopped in the middle of the road. He waved at the two paramedics who jumped out and as they ran towards the house a patrol car pulled up behind the ambulance.

James told the paramedics that Hannigan had been on the cocaine and booze and they then assessed the situation for themselves.

‘It’s a good sign that he’s breathing well,’ one of them said, ‘and it seems as though he’s gradually becoming more responsive. We won’t know if there’s serious internal damage until we get him to the hospital though.’

Stevens offered to go in the ambulance with him and James said that he and the patrol officers would carry out a quick search of the house since the warrant had been granted.

‘We need to find contact details for his relatives,’ he said. ‘And at the same time, we’ll take the opportunity to see if there’s anything incriminating to be found.’

After Hannigan was stretchered out, James informed the two uniforms that the injured man was a suspect in the murder of Rachel Elliott, and gave a brief explanation as to why.

‘We’re looking for anything that might be perceived to be relevant,’ he added.

He told one of them to search all the downstairs rooms and the other to check the bedrooms.

‘I’ll take the office upstairs,’ he said.

Hannigan’s mobile phone was found almost immediately on the sofa in the living room, but it was predictably password-protected.

James had better luck with the laptop on the desk in the office. It was already switched on and when he touched the mouse the screen came to life. He then spent the next twenty minutes going through the man’s email and social media accounts, internet search history and deleted files. It was virtually all work-related, though, and there was no mention of Rachel Elliott on anything he opened.

However, her name and telephone number were listed in an address book that James found in one of the desk drawers. Other contacts in there included Hannigan’s parents and Erika Chan.

The first call he made was to the parents, to tell them that their son had been rushed to hospital with a serious head injury. It was a landline number and the father answered.