A chilling horror film, Sauna explores the space between Christianity and paganism. The year 1595 - a long and brutal war is finally over. Brothers Knut and Erik, who are part of a commission marking the border between Finland and Russia, commit a terrible sin as they leave a young girl to die a horrible death. As the commission crosses the uncharted swamp, the girl returns to haunt them. Weary men find solace from the nameless village and find a sauna, the sauna where all sins are washed away.