The Russian crime-detective series "One" tells the story of a former police officer named Roman Odintsov. It has been 7 years since he left the force due to disagreements with his superiors and betrayal by loved ones, and subsequently divorced his wife. Odintsov is a reclusive loner who views the world with great distrust. However, when an old friend approaches him with a business proposition, the protagonist decides to accept it. He joins a team and little does Roman know that soon he will find himself involved in another investigation...