Chestnut (2024) Plot Summary & Ending Explained

After his death, the investigation uncovers a crucial piece of the puzzle: Simon had a twin sister, Astrid, who is revealed to be the one behind Kristine’s rescue. She had hidden Kristine to protect her from Simon, her psychopathic brother's, wrath. Astrid's connection to the crime confirms that she was the real savior, while Simon's twisted motives and actions were fueled by his traumatic past and mental illness.

The series concludes with Kristine finally being reunited with her mother, Rosa, and the case being closed. Thulin decides to move to the cybercrimes unit to spend more time with her daughter, while Hess contemplates returning to Copenhagen. Meanwhile, the fate of Linus Bekker, who was falsely accused of the murders, is left open—an innocent man released, but potentially vulnerable to returning to his disturbed ways due to his schizophrenia and obsession with the killer’s ideals.

In the final scenes, it is hinted that there might still be future threats, as Simon’s psychological influence, expressed through the chestnut figures and his obsession, leaves a lingering danger of more such crimes happening again. The series ends on a note that although Kristine is safe, the darkness that spawned the killer might not be entirely gone, hinting at a potential for future violence.