Hel (2010)

Piotr is a psychiatrist. He is on night duty when a boy is brought to his ward. It is Kamil, the son he hasn't seen in years. The boy disappears from the hospital as quickly as he appeared. However, Piotr decides to get in touch with him. He invites him to his place and introduces him to his beautiful young fiancée. After Kamil's visit, the woman realizes that Piotr is a mystery to her and that she really knows nothing about him. And Piotr does indeed hide a dark secret...