Ellery Queen, Master Detective is a 1940 American mystery film directed by Kurt Neumann and written by Eric Taylor. The film stars Ralph Bellamy, Margaret Lindsay, Charley Grapewin, James Burke, Michael Whalen and Marsha Hunt. The film was released on November 30, 1940, by Columbia Pictures.

Plot

John Braun, healthy and athletic model for his fitness enterprise, gets fatally ill and on the next day changes his will, leaving everything to his company. John locks himself up in his study, but Nikki goes to talk with him. She waits in the anteroom, but finds herself locked in and when they finally manage to open the door, they find Braun sitting at his desk, stabbed, and both the will and the murder weapon missing.