Markus returns home to care for his daughter when his wife dies in a tragic train accident. However, when a survivor of the wreck surfaces and claims foul play, Markus suspects his wife was murdered and embarks on a mission to find those responsible.
When a homeless Romani boy is arrested at the Danish border for possession of a missing public servant's passport, police inspector Carl Mørck and Department Q are tasked with finding the connection.
Over the course of a week, sisters Inger and Ellen find their relationship challenged on a highly anticipated coach trip to Paris. Inger reveals her struggles with schizophrenia to the group, receiving both pity and discrimination. On arrival, it soon becomes clear that Inger has a hidden agenda concerning a figure from her past, ultimately involving the entire group in her hunt for answers.
