Bergerac (1981)

S7E4 The Other Woman

During a round of golf, Charlie stumbles upon the lifeless body of Graham Hawkesworth buried in a sand trap. As the investigation unfolds, it is revealed that Graham was allegedly involved in an affair with a mysterious woman, making her the prime suspect in his murder. Suspicion quickly falls on Susan, but the truth is far more shocking. It turns out Graham fabricated the affair to provoke jealousy in his wife, who is the true murderer and now sets her sights on Susan as her next target.