When the clock struck seven, Wallander tried to get hold of Jörne, who had done the autopsy on Alexandersson, but in vain. He realised he was being impatient. The case of the dead man in the back seat of Stenberg's taxi was making him uneasy.

It was 7.58 when they assembled in the conference room. Rydberg reported that Martinsson still had a fever and a very sore throat. Wallander thought how typical it was that Martinsson should succumb to something like this when he was so obsessed by germs in general.

'OK, in that case it'll be you and me knocking on doors in Svarte today,' he said. 'You, Hansson, stay here and keep digging away. I'd like to know more about Alexandersson's son, Bengt, and how he died. Ask Rendel for help.'

'Do we know any more about that poison yet?' asked Rydberg.

'I tried to find out this morning,' Wallander said, 'but I haven't heard anything yet and I can't get a response from anybody.'

The meeting was very short. Wallander asked for an enlargement of the photograph on Alexandersson's driver's licence, plus several copies. Then he went to see Björk, the chief of police. On the whole, he thought Björk was good at his job and let everybody get on with their own work. Occasionally, however, the chief would suddenly become proactive and ask for a rundown on the latest situation in an investigation.

'How's it going with that gang exporting the luxury cars?' Björk asked, dropping his hands onto his desk as a sign that he wanted a concise answer.

'Badly,' said Wallander, truthfully.

'Are any arrests imminent?'

'No, none,' Wallander told him. 'If I were to go to one of the prosecutors with the evidence I have available, they'd throw me out immediately.'

'We mustn't give up, though,' said Björk.

'Of course not,' said Wallander. 'I'll keep working away. As soon as we've solved this case of the man who died in the back seat of a taxi.'

'Hansson told me about that,' said Björk. 'It all sounds very strange.'

'It is strange,' said Wallander.

'Can that man really have been murdered?'

'The doctors tell us he was,' Wallander said. 'We'll be knocking on doors today out at Svarte. Somebody must have seen him.'

'Keep me informed,' said Björk, standing up as a signal that the conversation was at an end.

They drove to Svarte in Wallander's car.

'Skåne is beautiful,' said Rydberg, apropos of nothing.

'On a day like this, at least,' said Wallander. 'But let's face it, it can be pretty awful in the autumn. When the mud's higher than your doorstep. Or when it seeps in under your skin.'

'Who's thinking about autumn now?' said Rydberg. 'Why worry about the bad weather in advance? It'll come eventually, like it or not.'

Wallander didn't respond. He was too busy passing a tractor.

'Let's start with the houses along the beach to the west of the village,' he said. 'We can go in different directions and work our way towards the middle. Try to find out who lives in the empty houses as well.'

'What are you hoping to find?' Rydberg asked.

'The solution,' he replied, without beating around the bush.

'Somebody must have seen him out there on the beach. Somebody must have seen him meeting some other person.'

Wallander parked the car. He let Rydberg start with the house where Agnes Ehn lived. Meanwhile Wallander tried to contact Jörne from his mobile phone. No luck this time either. He drove a bit further west, then parked the car and started working his way east. The first house was an old, well-cared-for traditional Skåne cottage. He opened the gate, went down the path and rang the doorbell. When there was no reply, he rang again, and was just about to leave when the door was opened by a woman in her thirties, dressed in stained overalls.

'I don't like being interrupted,' she said, glaring at Wallander.

'Sometimes it's necessary, I'm afraid,' he said, showing her his ID.

'What do you want?' she asked.

'You may find my question a little strange,' Wallander said, 'but I want to know if you've seen a man aged about fifty wearing a light blue overcoat walking along the beach in the last few days.'

She raised her eyebrows and looked at Wallander with a smile.

'I paint with the curtains drawn,' she said. 'I haven't seen anything at all.'

'You're an artist,' said Wallander. 'I thought you needed light.'

'I don't. But that's not a jailable offence, is it?'

'So you haven't seen anything at all?'

'No, nothing – that's what I just said, isn't it?'

'Is there anybody else here in the house who might have seen something?'

'I have a cat who likes to lie on a windowsill behind the curtains. You can ask him if you like.'

Wallander could feel himself getting annoyed.

'It's sometimes necessary for police officers to ask questions, you know. Don't think I'm doing this for fun. I won't disturb you any longer.'

The woman shut the door. He heard her turning several locks. He moved on to the next property. It was a relatively recently built two-storey house. There was a little fountain in the garden. When he rang the bell a dog started barking. He waited.

The dog stopped barking and the door opened. He was facing the old man he had met on the beach the previous day. Wallander had the immediate impression that the man was not surprised to see him. He had been expecting him, and was on his guard.

'You again,' said the man.

'Yes,' Wallander said. 'I'm knocking on the doors of people who live in houses along the beach.'

'I told you yesterday that I hadn't seen anything.'

Wallander nodded.

'People sometimes remember things afterwards,' he said.

The man stepped aside and let Wallander into the house. The Labrador sniffed him inquisitively.

'Do you live here year-round?' asked Wallander.

'Yes,' said the man. 'I was a doctor in Nynäshamn for twenty years. When I retired we moved here, my wife and I.'

'Maybe she saw something?' Wallander said. 'Assuming she's here?'

'She's ill,' said the man. 'She hasn't seen anything.'

Wallander produced a notebook from his pocket.

'Can I have your name?' he asked.

'I'm Martin Stenholm,' the man said. 'My wife's name is Kajsa.'

Wallander noted down the names and put the book back in his pocket.

'I won't disturb you any more,' he said.

'No problem,' said Stenholm.

'I might come back in a few days' time and speak to your wife,' he said. 'Sometimes it's better for people to say for themselves what they've seen or haven't seen.'

'I don't think there would be much point,' said Stenholm. 'My wife is very ill. She has cancer and is dying.'

'I understand,' Wallander said. 'In that case I won't come back and intrude.'

Stenholm opened the door for him.

'Is your wife also a doctor?' Wallander asked.

'No,' said the man. 'She was a lawyer.'

Wallander walked down the path to the road, then on to three more houses, none of which produced any information. He caught sight of Rydberg and could tell he had almost finished his quota of doors. Wallander went to get his car and waited for Rydberg outside Agnes Ehn's house. When Rydberg arrived, he had no positive information. Nobody had seen Göran Alexandersson on the beach

'I always thought people were curious,' Rydberg said. 'Especially in the country, and especially where strangers are concerned.'

They drove back to Ystad. Wallander didn't say a word. When they got back to the police station he asked Rydberg to find Hansson and bring him to Wallander's office. He then phoned the medico-legal unit in Lund and this time managed to get hold of Jörne. Hansson and Rydberg had arrived by the time he had finished the call. Wallander looked questioningly at Hansson.

'Any news?' he asked.

'Nothing that changes the picture we already have of Alexandersson,' Hansson said.