Craig stares back into the room. ‘He’s got two perfectly functioning legs. Yes, he’s confused, but there’s no medical reason why we can’t arrest him. We’ve had uniforms on the door, but you know as well as I do that we’ve had no power to stop him from walking out of the hospital. Now he’s under arrest, we can keep him here. Legally. We should have done so the moment he got out of that van – god knows why I didn’t.’

‘Have you got enough to charge him?’ Robin asks.

She pauses. ‘Not yet.’

Robin’s aware of what she’s not telling him: their evidence is still patchy. But now he’s been arrested, the police have the power to properly search his flat and workplace, even go through his computer. And who knows what they’ll find.

DC Grey is standing awkwardly a few metres away in the corridor. ‘Grey,’ Craig shouts, finding a suitable conduit for her frustration. ‘Have you chased the lab yet?’

‘No, no, I…’ and he scuttles off, mobile in hand.

‘Listen,’ Craig says sternly. ‘I can’t have you interfering like this. I am a DI, you are a DS. This is my case, my patch. You can’t be questioning my decisions in front of my team.’

Even through his anger, Robin knows she’s right. He would have had stern words long before Craig did, if someone had been undermining him in front of West. She outranks him, and his behaviour has been perilously close to insubordination. ‘You’re right, boss. I apologise,’ Robin replies, contrite, pushing his personal feelings aside. ‘Are you asking me to leave?’

‘No. I’m simply saying that you need to decide whose side you’re on. Either you want to get to the bottom of this case and have access to our investigation or you’re family, and you stay the hell away from me.’

Robin stops. He wants to clear Finn’s name. And the only way to do that is to play ball.

‘I want to find out what happened.’

Craig looks at him, trying to read his face for sincerity. ‘Fine,’ she says at last. ‘But if we find something that shows Finn is guilty of murder and this case goes to trial, you may be called to testify against your friend. You’re aware of that, right?’

Robin nods, silent. He’ll deal with that problem when the time comes. If the time comes.

Craig shakes her head in disbelief. ‘Then come with me and shut the fuck up. We have an appointment with a blood-spatter expert.’ She starts walking, and he follows. ‘I must be crazy,’ she mutters as they go.

The van is still cordoned off as a crime scene, SOCOs swarming round. Craig and Robin both show their IDs and are signed in by the scene guard; he hands them white suits, then points towards the silver vehicle.