The Alfred Hitchcock Hour (1962) : 3x2

Over the protests of his wife Elsa, Keith Hollin rents a beach house. Elsa dislikes the house and is disturbed by her husband's digging of a gravelike hole in the basement. She is further disturbed when she finds out that Keith is seeing a local girl named Rachel. When Keith tells Elsa that he wants to buy the house, she decides to foil his plan by contacting the wife of the current owner to tell her to not to sell. Keith, however, grows angry and kills Elsa. He buries her body in the basement, but is surprised when the police arrive. The police carry shovels and want to dig up the basement. The police tell Keith that Elsa discovered the wife of the house's owner was missing. She tipped off the police and they began an investigation. They called the house's owner in for questioning and he confessed to murdering his wife. He told them that he buried his wife in the basement of the beach house. The police are at the beach house to dig up the basement so they can find the body.