‘I’ve screwed up, Sam. Big-time.’ He went on to explain the potential contamination of discarded gloves which undermined the tiny speck of forensic evidence which linked Jason Waddington to the crime scene.

She was horrified. ‘Why hasn’t he been released?’

He sighed, and obliquely eyed the other diners, to make sure no one was listening. ‘Rigby has got my balls in a vice. She’s given me a week, until Thursday, to get a new suspect. We tried to make it easy on Waddington by not identifying him. But of course the name’s got out.’

‘That’s terrible.’ She reached out for his hand.

‘Not just for him. I feel bad for the investigative team. They’re my people, and they’re having to carry on following the Jason Waddington line, even though I know he’s very unlikely to have had anything to do with it.’

‘So have you got anything else to replace it with?’

He blew another sigh. ‘She was being poisoned. Probably. Delahaye is being very careful. There are still reasons why it might be accidental exposure, and none of the food or drink in either her house or the flat where she sometimes stayed has tested positive. But it keeps leading me back towards the family.’

‘It’s what you always told me, isn’t it? Most crime is committed within families. Abuse, domestic violence. It’s just the least likely to ever be reported.’

Gillard nodded. ‘Of course here, we’re talking murder and potentially, with this toxin, an earlier attempted murder. I just think it’s going to be really difficult to link the two because of the different MOs. One, a vicious and brutal attack which could have been committed by anybody, and the other a subtle and premeditated poisoning, which surely must have required some access to the woman as well as a knowledge of chemistry.’

‘Now, my news,’ Sam said. ‘This morning when I was being sick in the downstairs loo, her bloody cat was in the house.’

‘You’re joking!’

‘No, seriously. It was that ginger and white one, Napoleon. I saw it in the kitchen, sniffing around.’

‘But how can it get in?’

‘It must have climbed onto the garage roof, and from the ridge tiles it’s just a short jump through the casement window at the side.’

Craig was now looking at his phone, which he had just turned on. ‘Then we should keep it closed,’ he said, without looking up. She was disappointed. From long experience this would be the end of their romantic evening.

‘But Craig, we have got to have some air in the house. I already keep all the downstairs windows shut, but you know how stuffy the place is. And I seem to get so hot now.’

‘Mmm.’

She could see he wasn’t listening. ‘Craig?’

He glanced at her. ‘I’ll fit a couple of bars across it. When I get a mo.’ He was staring intently at the phone, shaking his head.

‘So, about the house move—’

‘Hey, Prisha Roy has been arrested for some ton-up drink-driving.’ He looked pleased.