Two crime scene cleaners, Leo and Elvis, stumble upon a hidden room while working in a secluded cabin. Inside, they discover a secret laboratory containing peculiar medical equipment and a bathtub filled with a strange fluid. To their surprise, they encounter Thale, a mysterious, mute woman with a tail, indicating she is a mythical huldra from Scandinavian folklore. As they try to make sense of the situation, the two men realize that Thale has been held captive and subjected to bizarre experiments.

As they delve deeper into the circumstances surrounding Thale's imprisonment, they uncover unsettling details about her captor and his motivations. Struggling with their moral dilemmas, Leo and Elvis must protect Thale from external threats and help her regain freedom. Their discovery leads to a series of events that transform their lives and challenge their perceptions of reality.