It is a story of a group of police officers from Murder Unit in Poland who deal with unsolved cases. The group tries to solve some inexplicable mysteries from the past, which pertain to the Forgotten Soldiers, the history of the Recovered Territories and other mysterious cases from the WWII period that have an impact on the present time. The series underlines the fact that behind every case there is a human being with all his weaknesses, desires, madness or love that make him commit the crime.