‘There were two mugs on the kitchen counter near where the kettle usually sat, both containing tea dregs, and two used teabags in an otherwise empty kitchen bin – all this goes towards consolidating our theory that Billy takes the welcome guest route in.’

‘When are you going to mention the little book?’ Dunning asked.

‘Now. A few weeks before she was murdered – boyfriend Dolan doesn’t remember exactly when, but he says between two and three weeks before – Rhian found something in a cloth tote bag that she’d taken into work with her. She swore that when she took the bag in, all that was in it was a scarf and a copy of the Daily Mail. When she took it home at the end of the day and unpacked it, she found a little hand-made book: white folded paper with staples in the middle, about five inches by five inches – stiff card, really, more than paper. Only eight pages in total if you didn’t count the cover; twelve if you did. There was nothing to suggest who’d put the book there, or what it meant. Most of the pages were blank, but on one towards the back, someone had handwritten the words, ‘I wonder if it hurts to live’ in black ink, cursive writing. Rhian had no idea what this meant, and described the experience of finding it in her bag as “creepy”. More later on these little books, since each of Billy’s victims received one in similar circumstances.’

‘Yes, let’s come to the books later,’ Kerensa Moore agreed.

‘The investigation into Rhian’s death soon established that, unless she was keeping something well hidden, there was no obvious reason for her to get herself killed,’ Grace Woolston went on. ‘No trouble at all at home, in the extended family, friendship circle, at work, with any of the families whose kids she babysat for – nothing. Boyfriend didn’t do it – he was at work surrounded by people all afternoon. He’s got no criminal record, there’s nothing amiss about him as far as we can tell, and he’s obviously devastated – DC Wing and his team said that wasn’t an act?’

James Wing nodded his confirmation.

‘Billy left his DNA on the mug he drank his tea from. We know it’s his because he did the same at two of the other three crime scenes – Linzi and Angela. Josh Norbury was shot before he got as far as making Billy his first cuppa, so there was nothing there. The DNA profile we’re assuming is Billy’s from three of the four scenes matched none on record, so we’re none the wiser. We’ve taken samples from anyone and everyone connected to all four victims, and there was no match for our Billy DNA. Things were looking bleak. But then, once all obvious avenues of investigation had been covered and had turned up nothing, a stroke of luck occurred.’