That Cold Day in the Park is a 1969 psychological thriller film directed by Robert Altman and starring Sandy Dennis. Based on the novel of the same name by Richard Miles and adapted for the screen by Gillian Freeman, it was filmed on location in Vancouver, British Columbia, where the events occur. The supporting cast includes Michael Burns, Luana Anders, John Garfield Jr., and Michael Murphy. The picture was screened at the 1969 Cannes Film Festival outside of the main competition.

Plot

Frances, a woman who had inherited her late parents' Vancouver apartment, notices a nineteen-year-old boy sitting in the rain in a nearby park and invites him inside. The boy does not speak but appears to understand everything. Frances allows him to bathe and eat, then buys him new clothes the next day. That night the boy visits his parents and younger siblings, then returns to his small houseboat with his older sister, Nina, and explains what has happened to him.