Emma Watson, David Thewlis and Ethan Hawke in Regression Photo: Courtesy of San Sebastian Film Festival
The film, which stars Emma Watson and Ethan Hawke, tells the story of a young woman who accuses her father of a crime that he has no memory of having committed. When a renowned psychologist (David Thewlis) is brought in to help him relive his memories, they uncover an even greater mystery.
Regression is due for release in the UK on October 9.
The festival has previously announced it will close with London Road. Read more of our coverage here.