‘His girlfriend?’

‘Ruth Bussey, she said her name was.’

Simon nodded. ‘He mentioned her. Not her surname, just as Ruth. What did she want?’

‘Same as him, by the sound of it. Told me her boyfriend was adamant he’d killed a woman called Mary Trelease . . .’

‘Right.’ Simon nodded.

‘. . . but that he couldn’t have, because Trelease is still alive. I thought she was deranged at first, so I asked a few background questions. The more she talked—’

‘The more you thought she seemed sane?’ Simon cut in. ‘Preoccupied, upset, but sane?’

‘Preoccupied’s an understatement. I’ve met human wreckage before, but this woman was in a worse state than anyone I’ve seen for a long time. Shaking with fear, crying one minute, then staring into the distance as if she’d seen a ghost, telling pointless lies that made no sense. She had something wrong with her foot, and claimed at first that she’d sprained her ankle. When I said it didn’t look swollen, she changed her story and said she had a blister.’

Simon paced the room, chewing his thumbnail as he often did when he was concentrating. ‘Seed was the opposite—not changeable at all. He was very controlled. At first I thought he had to be asylum material, but . . . he didn’t seem it, even though he was insisting on the impossible and wouldn’t listen to anything I said. Twenty-eight times, he told me something I knew couldn’t be true; tried to use logic, even, to make me believe it.’

‘How do you mean?’ asked Charlie.

‘I asked him to describe the woman he killed, which he did in great detail. Point for point, his description matched the woman I saw and spoke to this morning.’

‘You’ve met Mary Trelease?’ The idea made Charlie feel funny; she wasn’t sure why.

‘I have and Gibbs has. We’ve both seen her passport, her driving licence. Today she showed me the deeds of her house with her name on, all the paperwork from her solicitor from when she moved, her bank statements . . .’

‘Why so much?’ said Charlie. ‘Passport and driving licence should have been enough.’

‘I think she was worried one of us was going to turn up every day and ask her to prove all over again that she’s who she says she is. She gathered together a stack of stuff to show me how absurd the whole thing is. She acted like . . . like she was afraid I was trying to steal her identity or something.’

‘Afraid, literally?’

Simon considered it. ‘Yeah, underneath her chippiness, I reckon there was some fear there.’

Two frightened women. Charlie didn’t like the feel of this at all. ‘So how did you get dragged in? You said Seed saw Gibbs first?’ She waited to be told that Seed had at some point requested Simon’s involvement, asked for him by name. She wasn’t quite ready to believe this wasn’t all a cruel hoax aimed at her. If Ruth Bussey and Aidan Seed knew she and Simon were engaged . . .