He looked down at his watch. He had plenty of time, but he decided to set off walking down to Kapellgatan, where the doctor's office was. He was filled with dread.

The doctor was young. He was called Göransson and came from somewhere up north. Wallander told him about his symptoms: the fatigue, the thirst, the increased urination. He also mentioned his leg cramps.

The doctor's diagnosis was swift, and surprised him.

"It sounds like too much sugar," he said.

"Sugar?"

"Diabetes."

For a split second Wallander was paralysed. The thought had never occurred to him.

"You look like you weigh a little too much," the doctor said. "We'll find out if that's the case. But I want to start off by listening to your heart. Do you know if you have high blood pressure?"

Wallander shook his head. Then he took off his shirt and lay down on the table.

His pulse was normal, but his blood pressure was too high. 170 over 105. He got on the scale: 92 kilos. The doctor sent him for a urinalysis and a blood test. The nurse smiled at him. Wallander thought she looked like his sister Kristina. After she had finished, he went back in to see the doctor.

"Normally you should have a blood-sugar level of between 2.5 and 6.4," Göransson said. "Yours is 15.3. That's much too high."

Wallander started to feel sick.

"This explains your fatigue," Göransson continued. "It explains your thirst and the leg cramps. It also explains why you need to urinate so often."

"Is there medication for this?" Wallander asked.

"First we'll try to control it by changing your diet," Göransson said. "We also have to reduce your blood pressure. Do you exercise frequently?"

"No."

"Then you'll have to start right away. Diet and exercise. If that doesn't help we'll have to go a step further. With this blood-sugar level you're wearing down your whole system."