She looks at the space next to the Audi on the driveway, imagining Jon’s black Mazda sitting there. She knows where that car is now – impounded in the police garage, waiting to be examined by the forensics team.

She realises, her body growing hot, that they might find evidence of her. Of them.

Nine months ago, the two of them met in a deserted car park. Christmas, and they’d barely been able to catch a minute together. Jonathan had said Amy was more clingy than usual, not going out, not leaving his side. And this was the best they managed – a hasty excuse by him to go to the supermarket. No time to get to hers or to a hotel.

She hurried out of her car, ducking in the freezing rain and throwing herself into the passenger seat of his Mazda. The inside of the car was warm and muggy, suffocating air blowing out of the vents, steaming up the windows. But this wasn’t the slightest bit Titanic movie-perfect. It was awkward, clumsy – his seat rolled backwards, her straddling him, knees painful against the door and the centre console. But they laughed, and kissed, and—

Shit.

This is a ridiculous idea, sticking with the investigation. She is risking the job she loves, everything she’s spent so long working for. But this is important. That tryst in the car was the most adventurous they’d ever been. Something badly wrong happened in that hotel room, she knows it.

She’ll come clean, she will. Once they’ve found out what happened. Once she’s ensured first-hand that Butler’s thoughts aren’t taken off course. He’s already mentioned other cases they both need to look at. All it will take is an upweighting of one of those, and Jonathan’s death will be pushed to the side.

Freya feels tears threatening again, but pushes them away as the front door opens. There she is. Amy Miller is dressed in smart black jeans and a shirt, a posh coat over the top. Her hair is shining and blow-dried, and even from this distance Freya can tell her make-up is immaculate. She doesn’t look like a woman torn apart by grief.

Freya watches as Amy clicks her car open, climbs inside then drives off. She waits a few minutes, biding her time in case Amy comes back, then gets out and hurries across the road towards the house. Freya glances around quickly. She knows where Jon keeps the spare key, a chance remark from her a month ago where burglars had got into a house using the key found in a fake rock. Piss-taking followed when Jon revealed he did exactly the same thing.

She hopes he didn’t take heed of her warnings, and sure enough, she picks the key out of the plastic rock in the flower bed. She puts it in the door, and she’s in.