Busman's Honeymoon

Busman's Honeymoon was the British title of a 1937 novel by Dorothy L. Sayers and the 1940 movie based very, very loosely on it. The American title was Haunted Honeymoon. (A "busman's holiday" is when a man who drives a bus for a living takes his family on vacation and ends up driving the car the whole time, so for him it's no break from his usual routine.)

Lord Peter Wimsey and Harriet Vane, played by Robert Montgomery and Constance Cummings[?] in the movie, marry and go to spend their honeymoon at the country house where she grew up, Talboys, which he has bought as a present for her. What is supposed to be a break from their usual routine of solving crimes (him) and writing about them (her) turns into an investigation of how the man Lord Peter bought Talboys from ended up dead at the bottom of the basement steps with his head bashed in.