He was still speaking in the same monotone, hardly seeming to take a breath during the whole speech. His voice was also a bit too high and shrill, and Martin exchanged a hasty glance with Gösta.

'It sounds like you have quite a busy schedule,' said Gösta, 'but you see, it's important for us to talk with you. So we'd really appreciate it if you could give us a few minutes of your time.'

Morgan seemed to mull over this question for a moment, but then decided to acquiesce. He stepped aside and let them in, but it was obvious he didn't appreciate this interruption of his routine.

Martin was taken aback when they entered. The cabin consisted of one small room, which seemed to serve as both workroom and bedroom, and there was also a little kitchen nook. The place looked clean and neat, except for one thing. There were piles of magazines everywhere. Narrow paths had been cleared between the stacks to facilitate movement between the various parts of the room. One path led to the bed, one to the computers, and one over to the kitchen. Otherwise the floor was completely covered. Martin glanced down and saw that the magazines were mostly about computers. Judging by the covers the collection before them had been amassed over many years. Some magazines looked new, while others seemed well-worn.

'I see that you're interested in computers,' Martin said.

Morgan merely looked at him without confirming the obvious in his observation.

'What sort of work do you do?' asked Gösta to fill in the awkward pause.

'I design computer games. Mostly fantasy,' replied Morgan. He went over to the computers, as if seeking protection. Martin noticed that he moved with a clumsy, lurching gait that threatened to knock over one of the stacks of magazines as he passed. But somehow he managed to avoid doing so, and he sat down at a computer without causing an accident. He gave Martin and Gösta a vacant stare as they stood there in the midst of all those magazines. They were wondering how to proceed in questioning this odd individual. There was something not quite right about him, but they couldn't quite put a finger on it.

'How interesting,' said Martin. 'I've always wondered how anyone managed to create all those fantastical worlds. It must take a heck of an imagination.'

'I don't actually create the games. Other people do that, I just code them. I have Asperger's,' Morgan added matter-of-factly. Martin and Gösta exchanged another bewildered glance.

'Asperger's,' said Martin. 'Unfortunately I don't know what that is.'

'No, most people don't,' said Morgan. 'It's a form of autism, but it's most often accompanied by normal to high intelligence. I possess high intelligence. Extremely high,' he added without seeming to attach any emotion to the statement. 'Those of us who have Asperger's have a hard time understanding such things as facial expressions, metaphors, irony, and tone of voice. The result is that we have problems interacting socially.'

It sounded as though he were reading from a book, and Martin had to make a real effort to follow Morgan's lecture.

'So I can't create the computer games myself, since that would require me to imagine other people's feelings. On the other hand, I'm one of the best programmers in Sweden.' The words were a simple statement of fact, not coloured by either boasting or pride.

Martin couldn't help being fascinated. He had never heard of Asperger's before, and hearing Morgan explain it made him genuinely interested. But they were here to do a job, and they had better get on with it.

'Is there somewhere we could sit down?' he said, looking about the room.

'On the bed,' replied Morgan, nodding to the narrow bed standing against the far wall. Cautiously Gösta and Martin made their way between the stacks of magazines and sat down carefully on the edge of the bed. Gösta spoke first.

'We assume you know what happened on Monday at the Florins'. Did you see anything peculiar that morning?'

Morgan did not reply, but looked at them blankly. Martin realized that 'anything peculiar' might be too abstract, so he tried to reformulate the question in a more concrete way. He couldn't even imagine how difficult it would be to function in society without being able to interpret all the implied messages in human communication.

'Did you notice when the girl left the house?' he said tentatively, hoping that was precise enough for Morgan to answer.

'Yes, I saw when the girl left the house,' said Morgan and then fell silent, unsure whether there was anything more to the question.

Martin was starting to get the hang of things and said more precisely, 'What time did you see her leave?'

'She went out at ten after nine,' said Morgan, still in the same high, shrill tone of voice.

'Did you see anyone else that morning?' Gösta asked.

'Yes.'

'Who did you see that morning, and at what time?' said Martin in an attempt to anticipate Gösta. He sensed that his colleague was starting to get impatient with their odd interviewee.

'At a quarter to eight I saw Niclas,' Morgan replied.

Martin was taking notes of everything he said. He didn't doubt for a second that the times were exact.

'Did you know Sara?'

'Yes.'

Gösta now began to squirm, and Martin hurried to place a warning hand on his arm. Something told him that an emotional outburst would not have a beneficial effect as they tried to get as much information as possible out of Morgan.

'How did you know her?'

The question elicited nothing but an empty stare from Morgan, and Martin rephrased it. He had never realized before how difficult it was to be precise when speaking, or how much he normally relied on the other person to understand the essence of what he was saying.

'Did she come here sometimes?'

Morgan nodded. 'She interrupted my routines. Knocked on the door when I was working and wanted to come in. Touched my things. Once she got angry when I told her to leave, and she knocked over some of my stacks.'

'You didn't like her?' said Martin.

'She interrupted my routines. And knocked over my stacks,' said Morgan, and that was about as close as he could come to showing any emotion about the girl.

'What do you think of her grandmother?'

'Lilian is a nasty person. That's what Pappa says.'

'She says that you sneaked about outside their house and looked in the windows. Did you do that?'

Morgan nodded without hesitation. 'Yes, I did. I wanted to have a look. But Mamma got mad when I said that. She told me that I mustn't do that.'

'So you stopped doing it?' said Gösta.

'Yes.'

'Because your mamma said that you mustn't?' Gösta's tone was sarcastic, but Morgan didn't notice.

'Yes, Mamma always talks about what one should and shouldn't do. We practise things to say and things to do. She teaches me that even if somebody says one thing, it can mean something completely different. Otherwise I might say or do the wrong thing.' Morgan looked at his watch. 'It's ten thirty. I should get back to work now.'

'We won't bother you any longer,' said Martin, getting to his feet. 'Please excuse us for disturbing your routine, but as police officers we can't always take such things into account.'

Morgan seemed content with that explanation and had already turned round to the computer screen. 'Pull the door closed behind you,' he said, 'or it will blow open.'

'What an odd duck,' said Gösta as they slipped through the garden to the car they had parked a block away.

'I thought it was fascinating, I really did,' said Martin. 'I've never heard of Asperger's before, have you?'

Gösta snorted. 'No, that's not something we had back in my day.

There are so many weird diagnoses nowadays. Personally I think the term "idiot" goes a long way.'

Martin sighed and got into the driver's seat. Gösta was certainly short on empathy, that's for sure.