I got out of the way as Zachary, looking a bit wild-eyed, was herded into the kitchen area by Carey. He’d be looking to get names and addresses of James Gallagher’s friends, and if possible, family as well as establishing Zach’s whereabouts at the time of the murder. You want to do that sort of thing fast before everyone has a chance to co-ordinate their stories. Guleed would be upstairs hunting out any useful diaries, phone books, laptops and anything else that would allow her to expand James Gallagher’s acquaintance tree and fill in the gaps in the timeline of his last movements.

I glanced around the living room. I guessed the house must have come ready furnished because it had that decorated out of a catalogue feel although, judging by the sturdiness of the furniture and the lack of laminated chipboard, it was probably a more expensive catalogue than my mother would have used. The TV was big and flat but two years old. There was a Blu-Ray player, an X-Box but no cable or satellite. I checked the simulation oak shelves beside the TV; the collection was a bit ostentatiously foreign, newly remastered Godards, Truffauts and Tarkovskys. Kurosowa’s Yojimbo was lying sacrilegiously on top of its case, ejected in favour of, judging from the case lying on the floor by the TV, one of the Saw movies.

The original fireplace, a rarity given that the ground floor must have been a coach house, had been bricked up and plastered over but the mantelpiece remained. Perched on it was an expensive Sony mini-system with no iPod attached – something else to look for – an unpainted figurine, a deck of playing cards, a packet of Rizlas and an unwashed cup.

Over in the kitchen area Carey had Zach settled at the table while he pottered around making proper coffee and having a rummage through all the cupboards and shelves for good measure.

If you’re a professional cleaner, like my mum, one of the ways you make sure you get the dust out of the corners is to use a moist mop and swirl it along the skirting board. All the crud gets rolled up into little damp balls, you wait a bit for them to dry and then you hoover them up. It leaves a distinctive swirling pattern in the carpet which I found behind the TV. It meant that James and Zach were not cleaning their own home and that I was unlikely to find anything useful in the living room. I headed for the stairs.