I really enjoyed how Karin Alvtegen subverts expectations in that one. For a long stretch, you're convinced it's a classic missing-person thriller where the friend, Daniella, is the obvious victim of foul play. The main character, Axel, is riddled with guilt over a past incident, and the narrative pushes you to believe he's either being framed or is an unreliable narrator about his own actions.
The actual twist, for me, was that Daniella isn't dead at all. She orchestrated her own disappearance to frame Axel, meticulously planting evidence and manipulating his psychological state as revenge for the childhood accident that left her brother severely disabled. It shifts the entire book from a 'what happened to her' mystery to a chilling 'how far will she go' character study. The tension becomes about whether Axel can prove his innocence against a phantom accuser who's always several steps ahead.
Alvtegen is great at these psychological traps, where the real crime isn't a murder but a meticulously planned destruction of a life. It makes you re-evaluate every earlier interaction between them.