Murder Most Foul

After being the only holdout in a jury that was ready to convict a man of killing his fellow lodger, Mrs. McGuinty, Miss Jane Marple (Dame Margaret Rutherford) sets out to find the real killer. She finds that the dead woman had a particular interest in a theater company, the Cosgood Players, run by H. Driffold Cosgood (Ron Moody). She no sooner manages to get an unpaid position with the company than one of the actors, George Rowton (Maurice Good), is poisoned and dies minutes before a performance. Miss Marple is certain that it's the same person responsible for both murders and when another member of the company is killed, Miss Marple is convinced that it she who was the intended victim.