Sebastien is a psychological horror story about dark secrets destroying people and their families from the inside out.

Following the death of her husband, Abigail sets off on a journey to reinvent her life and falls into a passionate affair with the artist Max, a longtime friend.

Three people gather for an "uncoupling celebration" arranged by a struggling writer and his mistress. When the power goes out during a thunderstorm, the deepest truths are revealed, changing each person's life forever.