Warsaw, 1909. Arthur Herling makes an assassination attempt on a Russian police official and his family. During the action, the officer's daughter is killed and his wife is maimed. The wounded militant is arrested. Tormented by remorse, Herling agrees to cooperate with the tsarist authorities as a provocateur. Into his cell comes Adam Tanski, suspected of having contacts with the wanted conspirator Andrzej Woyda. One day, while being transported in a prison ambulance, Herling kills the guards. Accompanying him, Adam urges him to escape to the mountains.