"Alfred Hitchcock Presents" Back for Christmas (1956)

Herbert is digging in his basement when his wife Hermione calls him upstairs to eat. She thinks he is making a wine cellar, but he is really planning to kill her and bury her in the basement. At lunch, Hermione goes over all the arrangements she has made for a business trip to California that they are about to take together. Several friends then come over to visit, and after they leave, Herbert looks for the opportunity to put his plan into practice.