‘He said it was helping. He said it calmed him down.’

Robin holds the small plastic bag up to Sophie’s face. ‘And where did you get it from?’ Sophie pushes her lips together and shakes her head. ‘This is no time for protecting your dealer, Sophie!’ Robin shouts. ‘We need to know what was in here. We need to know what he took.’

‘I don’t know!’ Sophie cries out. ‘He got it from someone at uni.’ Tears are streaming down her face and Robin turns away, exasperated.

‘I need to phone Craig,’ he growls and walks out of the flat, into the bleak concrete corridor.

The phone rings and Robin waits. Craig answers without pleasantries.

‘Have you found anything?’

‘The flat’s a mess. It looks like Finn hasn’t been functioning properly for a while.’ Robin looks at the bag in his gloved hand. ‘And a small quantity of LSD.’

‘LSD? Seriously?’ Craig exclaims.

‘Yes, apparently he was microdosing to cope with his anxiety and depression—’

‘But he could have got the amount wrong,’ Craig finishes for him. ‘Would explain a lot. One of our DCs managed to get close to the door and plant a listening device, but all we’re getting is garbled nonsense.’

‘You’re thinking Finn’s at the tail end of a bad trip?’

‘Maybe, yes.’ There’s a long pause, and Robin fills in the gaps. A bad hallucination, and who knows what Finn imagined. God knows what he might have done to Simon Sharp. ‘Bring it back,’ Craig says at last, ‘and we’ll get it rushed to the lab for testing. See what nasties might have been included.’

Robin signs off the call and rejoins the others in the flat. The three of them are still in the living room. Sandra has her arm around an ashen-faced Josie, who is holding a notebook in her hand. On the sofa, Sophie is crying quietly. They all look up when Robin comes back in.

‘No change,’ he says, and they look away, disappointed. He points to the notebook. ‘What have you got there?’

Josie flicks through the pages. ‘Oh. No. Sorry. This was on the side, one of Finn’s weather record books.’ She looks at it, almost reverently. ‘I have boxes of these at home. I’m surprised he still does this.’

She holds it out to Robin, and he runs his finger down the page. Temp. Dew point. Humidity. Wind speed. Rainfall. Air pressure. And their corresponding numbers. He glances towards the window; outside he can see an array of strange-looking instruments attached to the wall on a pole. He remembers Finn doing this as a kid, excitedly showing Robin his first weather station, Robin baffled by his enthusiasm. The technology has obviously improved since then, even if his method of record-keeping hasn’t, and Robin feels a sudden wave of sadness.

He returns the notebook to Josie. ‘We need to be getting back,’ he says, quietly.