Anna Oster is a mysterious and attractive commissioner with the Criminal Division of the Warsaw Police. Owing to her exceptional instinct, Commissioner Oster solves complicated criminal cases, collaborating with her younger work partner Piotr Tarkowski. As Anna starts to work for the Division, people start to ask questions. What are secrets of her past? What events had an impact on the life of the Commissioner? Each episode shows another criminal case solved, bringing us closer to unravelling the mystery of the protagonist.