"Alfred Hitchcock Presents" Nightmare in 4-D (1957)

Harry Parker in apartment 4-D reads a lot of pulp fiction and watches a lot of late-night TV. That lends an air of inauthenticity to the story he tells his wife in the morning about what happened at two A.M. It seems the blonde in 3-D needed him to play Sir Galahad. At two A.M., she has a man in her apartment. And he's dead. "Miss Elliot, I can't get involved in a murder," says Harry. "I'm a married man." But it isn't long before he finds himself helping her take the corpse down to the basement. Was the whole thing a dream?