‘The witness is certain,’ he said, hoping that would satisfy his colleagues. The important thing now was to reach Erica as quickly as possible and have a talk with Nathalie. Everything else could wait. Besides, they had the boat. According to the expert that Gösta had talked to, it was not only possible but very likely that Sverin’s boat had drifted from Gråskär when it ended up stranded in that inlet.

In Patrik’s mind, a plausible chain of events had begun to unfold. Mats had gone out to visit Nathalie, and for some reason she had then accompanied him in his boat to Fjällbacka. They had driven to Mats’s flat, where she had shot him. He had trusted Nathalie, so he didn’t hesitate to turn his back on her. Then she had gone back to the harbour, taken Sverin’s boat to Gråskär, and let it go from there, causing it to drift off until it got stuck and was later found. That much was crystal clear. Except that Patrik still didn’t have any idea why Nathalie would want to kill Mats and possibly also her husband. And why did they leave Gråskär and go back to Fjällbacka in the middle of the night? Did it have something to do with the cocaine? Had Mats been involved in business transactions with Nathalie’s husband? Did the unidentified fingerprint on the bag belong to her?

Patrik stepped even harder on the accelerator. Now they were racing through Fjällbacka, and he slowed down a bit when he almost ran into an elderly man who was crossing the street near Ingrid Bergman Square.

He parked the car at the harbour near the Coast Guard vessel and jumped out. He was relieved to see that Peter had already started up the motor. Konrad and Petra trotted after him and jumped on board.

‘Don’t worry,’ Konrad said. ‘At this point, it’s all speculation, and there’s no reason to believe that your wife is in danger, even if your theory turns out to be correct.’

Patrik glanced at him as he held on to the railing of the boat, which was speeding out of the harbour faster than was normally allowed.

‘You don’t know Erica. She has a talent for sticking her nose into everyone’s business. Even people who have nothing to hide think that she asks too many questions. You might say that she’s really persistent.’

‘She sounds like a woman after my own heart,’ said Petra, staring with fascination at the archipelago they were traversing.

‘And besides, she’s not answering her mobile,’ said Patrik.

No one said a word for the rest of the crossing. They saw the lighthouse in the distance, and Patrik felt his stomach lurch with fear as they neared the island. He couldn’t stop thinking about the other name for Gråskär, the name that the locals called it: Ghost Isle. And why it had got the name.

Peter slowed down and steered the boat over to the dock, next to the wooden motorboat that belonged to Erica and Patrik. There was no one in sight, either living or dead.

Everything was going to be fine. They were together. She and Sam. And the dead were keeping watch over them.

Nathalie hummed as she stood in the water holding Sam in her arms. It was a song that she had always sung to him when he was younger and couldn’t sleep. He lay in her arms and felt so light because the water was helping to carry him. A few drops splashed upon his face, and she carefully wiped them away. He didn’t like getting water in his face. As soon as he was feeling better, she was going to teach him to swim. He was old enough now to learn to swim and ride a bike, and soon he’d be losing his baby teeth. Then he’d have a big gap in his teeth, showing that he would soon leave the first years of childhood behind.

Fredrik had always been impatient with Sam and demanded too much of him. He thought that she coddled him, claiming that she wanted him to remain a child. Fredrik was wrong. She wanted nothing more than for Sam to grow up, but he had to do it at his own pace.

Then he had tried to take Sam away from her. In that arrogant voice of his, Fredrik had said that the boy would be better off with a different mother. The memory started encroaching, and she hummed louder to make it go away. But those terrible words had already crept into her soul, drowning out the song. The other woman would be better, he had told her. She was the one who would be Sam’s new mother and accompany him and Sam to Italy. Nathalie wasn’t going to be his mother any more. She was going to disappear.

Fredrik’s face had been filled with such smug satisfaction that she hadn’t doubted for a moment that he meant what he’d said. How she hated him. Anger began growing somewhere deep inside of her and then took over her whole body before she could stop it. Fredrik had got what he deserved. He couldn’t hurt them any more. She had seen his rigid expression. She had seen the blood.

Now she and Sam could live in peace here on the island. She looked down at his face. He was sleeping. No one was going to take him away from her. No one.

Patrik asked Peter to wait in the boat. Then he went ashore with Konrad and Petra. On the table in the open-sided boathouse they saw that someone had served coffee there. When they walked past, several seagulls flew up from a plate full of buns.

‘They’re probably in the house,’ said Petra, taking a good look around.

‘Come on.’ Patrik was impatient, but Konrad gently took him by the arm.

‘I think we need to be a bit cautious now.’

Patrik realized that he was right. He headed for the house, walking calmly even though he wanted to run. At the house, they knocked on the door. When no one answered, Petra leaned forward and knocked harder.

‘Hello?’ she called.

Still not a sound from inside. Patrik pushed down the handle, and the door swung open. He took a step forward then nearly backed into Konrad and Petra as the smell overwhelmed him.

‘Shit,’ he said, putting his hand over his nose and mouth. He had to swallow several times in order not to throw up.

‘Shit,’ echoed Konrad from behind him. He too looked as if he were fighting back nausea. Only Petra seemed unperturbed, and Patrik cast an astonished glance in her direction.

‘I’ve got a weak sense of smell,’ she told him.

Then Patrik entered the house and immediately caught sight of the person lying on the floor.

‘Erica?’ He ran over and dropped to his knees. With his heart in his throat, he put out his hand to touch her. She stirred and let out a groan.

He said her name over and over, and she slowly turned her head to look at him. Only then did he see the wound at her temple. With an effort she lifted her hand to touch it, and her eyes opened wide when she saw the blood on her fingers.

‘Patrik? Nathalie … she …’ Erica began sobbing and Patrik stroked her cheek.

‘Is she okay?’ asked Petra.

Patrik motioned with his hand to indicate that she was going to be all right. Then Petra and Konrad went upstairs to see what they could find up there.

‘The place seems to be empty,’ said Petra when they came back. ‘Have you checked in there?’ She pointed at the closed door behind Erica.

Patrik shook his head, so Petra cautiously stepped around them and opened the door.

‘Bloody hell. Come and look.’ She motioned to them, but Patrik stayed where he was and let Konrad follow his colleague.

‘What do you see?’ asked Patrik, glancing at the partially open door, which blocked his view of what was inside.

‘Whatever the smell is, it’s coming from inside this room.’ Konrad came out, holding his hand over his mouth and nose.

‘A dead body?’ For a moment Patrik thought it must be Nathalie lying inside there, but then a thought occurred to him that drained all the colour from his face. ‘Is it the boy?’ he whispered.

Petra came out of the room too. ‘I don’t know. There’s nothing in there now. But the bed is a horrible mess and it stinks to high heaven. Even I can smell it.’