All Night Long (1981)

Executive George Dupler loses his temper and is demoted to the night manager at a 24 hour drugstore. After he suggests to his teenage son Freddie that he stop having an affair with suburban housewife Cheryl Gibbons, who is a distant cousin, Cheryl tries to seduce George. At home, in front of his mother, Freddie accuses his dad of stealing his girl, because he found Cheryl serving George a meal in the middle of the night, while her husband Bobby was on duty at the fire station. George then separates from his wife Helen, quits his job, moves into a warehouse, and asks Cheryl to move in with him
Jean Claude Tramont
Gene Hackman, Barbra Streisand, Diane Ladd, Dennis Quaid, Kevin Dobson, William Daniels, Ann Doran, James Nolan, Judy Kerr, Robin Reed, Annie Girardot
tt0082001