A rich man's last wish is that Miss Marple solve a crime. However, Miss Marple has not been told what the crime is. Instead, she is sent on a coach tour with her nephew, Raymond West. However, Miss Marple soon realizes that the rest of the guests on the tour are connected to Verity Hunt, who went missing from her nun's sanctuary during the war. Miss Marple and Raymond must now put the pieces together to fulfill her promise to her deceased friend.