‘He’s in the wine cellar,’ Helena replies. ‘If you turn on the kettle, Alvin, I’ll go and get him.’

‘Tell him I’m in a hurry. And make sure he brings my phone so I can go.’

‘Are you working tonight?’ Karen asks after Helena leaves.

‘No, I’m going out with some friends. But I can’t leave until I have my phone. This is the second time this has happened. We have the same kind,’ he adds and holds out the iPhone. ‘Except mine is new, obviously.’

Something about what he just said makes Karen go cold. Suddenly, her mind is rewinding the past few days. Every meeting, every conversation, every piece of information. And everything points to the same conclusion.

Impossible. And yet.

When she asks the next question, the howling of the wind outside and the crackling of the fire seem to subside. The world goes quiet to make sure she doesn’t miss a word, not a nuance of Alvin’s answer.

‘So he took your phone by mistake,’ she says as casually as she is able. ‘That sucks. When was the other time it happened?’

‘Christmas Day,’ Alvin says with a sigh. ‘Dad accidentally took mine and then, as if taking it wasn’t bad enough, he dropped it in the toilet right before we left. He let me borrow his but spending all day at work without my phone was a proper drag. I sit vigil at the nursing home in Lysvik,’ he adds.

‘Wow, well, I can see why you’d want your own apps. But at least you could still call your friends.’

‘We only use text.’

‘You didn’t call anyone? Not even your mum?’

‘Maybe, I guess. Actually, yeah, I did do that . . . Dad made me promise to call Mum to wake her up at eight. But how did you know . . . ?’

Alvin looks confused and then the sound of William Tryste’s voice reaches them.

‘Here’s your phone, Alvin. Now get going, your friends are waiting for you outside.’

And as Alvin snatches up his phone and makes a beeline for the door, Karen notices Helena looking helplessly from her husband to Karen and back before turning and following her son.

William stays in the doorway with his arms folded. Their eyes meet briefly. Neither one of them is happy about this unexpected revelation, she realises. And yet, there it sits, like a stinking pile of truth in the middle of the floor. William Tryste wasn’t the one who called Helena from Lysvik at the exact same time the murder of Fredrik Stuub was taking place. Alvin was.

You fucking prick, she thinks to herself. You used your own son to make up an alibi.

‘Why?’ she says calmly.