Who Killed Doc Robbin? (1948)
Plot: After an explosion at the laboratory home of Hugo 'Doc' Robbin, his secretary, Ann Loring, is put on trial for his murder. As the trial begins, five children burst into the courtroom, claiming to have crucial information. The children's story, told in flashback, details their adventures at Doc Robbin's gloomy home with their inventor friend, Dan 'Fix-It' Cameron, who is then arrested on suspicion. The kids, determined to prove Dan's innocence, sneak into the mansion to find the "atomic firing chamber"—a vague super-scientific device—which they believe holds the key. The film becomes an "Old Dark House" comedy, with the children encountering secret passages, spooky happenings, seemingly murdered bodies, and a menacing gorilla as they try to solve the mystery.
