A figurine made of chestnuts is found at the scene of a grisly murder; from this creepy clue, two detectives hunt for a killer linked to a politician's missing child.
Hess uses unorthodox methods to prove a theory about the Hartung case. The detectives chase a lead linked to a text message. Rosa faces another threat.
Neither Thulin nor Hess can stop thinking about the unanswered questions hanging over their case. Rosa's career unravels as a childhood memory surfaces.
