The tiny button with the blue and red superhero was lying on the floor only inches in from the edge of the clear-glass bin. Had it just come loose or had someone grabbed the boy violently? Someone who had happened to come in and see their chance. Someone who lived in the building.

She went back into the stairwell and walked over to the blue felt board with the names of the residents, while pulling out her phone and finding the number of Sverker ‘Klippan’ Holm.

‘Hi there. How are you doing? I heard you stopped by my lovely hometown.’

‘The jury’s still out on whether it’s really all that lovely. And while we wait for it to return its judgement, I need your help with doing a quick check of the people who live in this building.’

‘No problem. What’s the address?’

‘Vintergatan 2A.’

‘Wow, that really is my old ’hood. Did you know I took my first trembling steps in a garden on Trumpetgatan 8, just a few minutes from there? It’s obviously changed quite a bit, but—’

‘Klippan, not now,’ Lilja broke in, realizing she should have called Astrid Tuvesson or Ingvar Molander instead.

‘All right, but just say the word if you need a suggestion for a good place to go for lunch. If you ask me, that would have to be schnitzel and—’

‘Klippan, for fuck’s sake!’ Her voice echoed all the way up the stairwell; it was an effort for her to lower it again. ‘I think he might still be in the building, with one of the neighbours, and I don’t know about you, but for my part, the last thing I want is to get there too late.’

‘Well, there’s no convicted paedophile living there,’ Klippan said in a tone that did nothing to hide that he was insulted.

‘Right now, a suspected one would be plenty,’ Lilja said in a tone that did nothing to hide that she didn’t give a flying fuck.

‘None of that description either. But there’s someone on the second floor who works as a nursery teacher at the Sunflower not too far—’

‘Do you have a name? I need a name.’

‘Yes, if you would let me finish, his name’s Björn Richter, he’s thirty-two years old and lives, as far as I can see, alone with all his—’

‘With all his what?’ Lilja’s eyes were caught by a small rust-red stain on the wall by the stairs leading down to the basement.

‘Wait, I just have to check if it’s him.’

It wasn’t that she’d failed to notice it before. She had just assumed it was one of the hideous stipples.

‘Yes, that checks out. Talk about creepy—’

‘Klippan, would you mind telling me what you’re up to?’

But this particular spot was slightly bigger than the rest and smeared on one side, which indicated it had been made later.