‘How come you knew about Tic-Tac’s door?’

Knut snorted. ’Doesn’t everybody? The door was there when I went to Fredheim High as well, twenty years ago. It’s probably been there since the whole thing was constructed.’

Yngve nodded and made a note on the pad before him.

‘When you did your quick search for Mari, did you look for her on the second floor?’

‘I went up there, yes. Briefly. I couldn’t see her, so I went back down again and decided to see if I could find her in another section of the school.’

‘Did you see anyone else while you were doing that?’

Knut shook his head.

‘What did you do after you left the school?’

‘I hurried back to my car and waited a little while. Then I left.’

Yngve cursed under his lips. The CCTV cameras were only facing the school entrance, not the surrounding areas.

‘How long is “a little while”?’ he asked.

‘A good ten minutes or so. I figured Mari had got a ride home with someone else without cancelling my call. I didn’t want her to have to pay for it, so I just deleted the booking.’

Yngve sighed heavily. Therese had spoken to the taxi company before they’d brought Knut in. They could confirm that Knut had been on duty on the night of the school murders, but they didn’t have any records of him completing any fares between 11.00 and 12.16. Now they knew why.

‘What I’m dying to know, Knut, is why the hell you didn’t come forward with this information before I dragged you in here. You were on the school premises literally minutes before two teenagers were murdered. You didn’t think we’d need to talk to you?’

A line of sweat had formed on Knut’s upper lip. ’I was only there for a couple of minutes,’ he said tentatively. ‘Five maybe. I didn’t see anything. Didn’t hear anything, either. I figured you wouldn’t be bothered with my statement.’

‘You figured wrong.’

‘Well, I’m sorry,’ he said. ‘I thought it would be a waste of your time.’

‘You could have saved us a lot of time. And trouble.’

Yngve thought about his sleepless night in the car and wanted to swear at the man in front of him, but he managed to hold back. ‘God knows how many hours we’ve been working trying to figure out who that person was on the surveillance tapes.’

‘Again, I apologise.’

Yngve rubbed his eyes.

‘After you’d come out of the school, and while you were waiting in your car, did you see anyone then?’

‘No, it was raining quite heavily. Which was why I didn’t want to waste any more time just sitting there.’

‘It was quite service-minded of you,’ Yngve said, ‘to go in and look for Mari like that. Would you have done that for any other customer?’