The pair of swans was brooding; the female sitting heavily on the nest of seagrass, the male circulating warily around her. In a good month’s time, the fort would have a new clutch of fuzzy little fledglings that would stick close to their mother to survive the first critical weeks.

Mads smiled at the thought.

He continued along the embankment, past one of the old white-and-red-striped navigation markers, towering on poles atop the ridge. The first bachelor party of the season was taking place around noon today. Mads had already prepared the stations of their treasure hunt in the underground corridors, but an impulse made him walk the route again.

The air between the casemate’s thick concrete walls felt cool, as he descended the winding stairs to the low-slung ceiling of the cellar level. His footsteps echoed, as if somebody was walking behind him in the shadows. When he passed the old cell door with a red cross on it, the sound distortion felt so real that he had to turn around and look back. But of course no one was there, only the ghosts in his own head.

Mads checked all twelve of the stations and made sure that the ropes were lashed and the flashlights charged, before he walked back out into the light. He could just fit in a couple of hours in the workshop before the guests arrived. On his way back to the commandant’s building, he passed the solitary wooden yawl, which was still moored to the dock. It didn’t worry him. Still, he locked the main door behind him. No need to risk being disturbed.

To be on the safe side he also locked the door to the workshop. He hung his windbreaker on the doorknob, leaving his phone in a pocket of it, and switched the sound system on so Tchaikovsky’s Sixth Symphony filled the room.

The prospect of an hour of absolute peace and quiet for his next project made Mads breathe a sigh of relief. He took a plastic-wrapped package out of the refrigerator and set it on the workbench. Carefully he unwrapped it, filled a bowl with water, and got the scalpel ready.

CHAPTER 3

Anette watched the parents sitting on the pink sofa and reluctantly remembered the British couple who had lost their little girl while vacationing in Portugal. Despite years of searching, she had never been found. Eventually some people had begun speculating whether the parents themselves had been behind her disappearance.

“The letter was left on the kitchen table,” Henrik explained, pulling his wife closer, as if he could physically protect her from the words coming out of his mouth. “We didn’t notice it until we realized that Oscar was missing, just thought it was a homework assignment or something like that.”

“And it isn’t?”

They both shook their heads.