Seeing this movie when I was younger gave me a real fright. Bryant Haliday portrays "The Great Vorelli," a ventriloquist who seems successful but also rather questionable, along with his puppet “Hugo.” After encountering the affluent "Marianne" (Yvonne Romain), he becomes fixated on her money and finds a way to put her into a coma. Her boyfriend, "Mark" (William Sylvester), a journalist, grows wary and starts looking into things. His inquiries uncover a shadowy history for the performer—a situation made worse by the discovery of his girlfriend "Magda’s" body, which turns out not to be an isolated incident. Up until that point, the film was genuinely unsettling and enjoyable. The woman then comes out of her coma, chooses to marry "Vorelli," and it becomes apparent that “Hugo” might not be as inanimate as he appears. That's when the tension disappears; the plot falters, relying too much on conversations, and the resolution feels abrupt and unresolved. Haliday does a decent job, but the other actors don’t quite measure up—their performances are overwrought, and the orchestral music doesn’t really work. Time hasn’t helped maintain the feeling of danger here; it's unfortunate.

Source on TMDB