The Twilight Zone - The Dummy

Jerry Etherson has a reasonably successful nightclub act as a ventriloquist but has one major problem: he believes his dummy Willie is a sentient being who speaks to him and manipulates his life. His agent Frank thinks Jerry needs psychiatric help and tells him he has no future in the business if he doesn't do something about his delusions. Jerry decides to lock Willie in a trunk and try his act with a different dummy. Willie has plans of his own however