Jonas is a Copenhagen homicide scene photographer, happily married, with two kids. One day, his car stalls, another car slams into him, runs head on into a third car and flips into the ditch. The other driver, Julia, is critically injured. He visits her in the hospital and is greeted by her family, who assumes he must be the Sebastian she told them about, the new fiance she met in Vietnam.

A closed psychiatric ward somewhere in Denmark. The doors are locked, the windows impossible to break. Alex is running down the corridor, towards the light, but precisely as she is about to reach freedom, she is swept away. Dragged away. Strapped down. Medicated. But to Alex surrender is not an option. In Darkness is a story about a woman's raging struggle against a system in the process of destroying her.

Eva, an idealistic prison officer, is faced with the dilemma of her life when a young man from her past gets transferred to the prison where she works. Without revealing her secret, Eva asks to be moved to the young man’s ward – the toughest and most violent in the prison. Here begins an unsettling psychological thriller, where Eva’s sense of justice puts both her morality and future at stake.