Devil Doll

Stage hypnotist The Great Vorelli and his dummy Hugo perform before a packed London audience. The audience notices a growing tension between Vorelli and his puppet, which he keeps locked away in a cage between acts. American reporter Mark English is assigned to cover the act and convinces his girlfriend Marianne Horn to attend the show.

During the show, Vorelli selects a volunteer and hypnotizes Marianne, making her dance the twist. The hypnotism appears to have a real effect, until Hugo seems to move on his own during the ventriloquism routine. Mark watches closely, suspecting there is more to Hugo than a simple dummy.

To get a closer look at Hugo, Mark convinces Marianne to invite Vorelli to her aunt's charity ball. Onstage during the ball, Hugo moves to seize a knife from a buffet and tries to stab Vorelli, but the act continues as if nothing happened. Guests believe the stabbing was part of the illusion.

Mark secretly examines Hugo and discovers there is no mechanism or operator to power the puppet. He realizes Hugo is truly a lifelike puppet controlled by something unseen. This discovery shakes his confidence in Vorelli's stage craft.

That same night, Vorelli uses hypnotic power to subdue Marianne as she stays at the mansion. He rapes her, and in Mark's room Hugo suddenly appears and pleads for help before vanishing. The night ends with Marianne in a state of shock.

Marianne lapses into a semi-conscious coma that doctors cannot alleviate. In a lucid moment she tells Mark that 'He keeps calling me' and to 'Make him stop.' Mark links her condition to Vorelli's hypnotic control and vows to uncover the truth.

Mark consults a colleague and learns that Vorelli was once a medical doctor dabbling in Eastern magic and was disbarred. The revelation suggests a dangerous blend behind the illusion. This drives Mark to pursue the former associates of Vorelli.

Through a former assistant named Mercedes in Berlin, Mark learns that Hugo worked for Vorelli in 1947 and was hypnotized into a pain-free state. Mercedes recounts how Vorelli stabbed Hugo on stage, and Hugo reacted with pain only later. The incident was ruled an accident, and no one believed Mercedes's story, despite a theatre worker testifying the puppet moved after Hugo screamed.

A theatre worker testifies that the dummy moved immediately after Hugo screamed in pain, contradicting the illusion that Hugo is merely a puppet. The story supports Mercedes's claim that Hugo's soul was involved in the act. Mark's confidence grows that Vorelli engineered Hugo's death.

Vorelli's current lover Magda grows enraged at the rape and threatens to expose him. Vorelli taunts Hugo into murdering Magda with a knife, exploiting the chaos as stage crew are elsewhere. The attack demonstrates the depth of Vorelli's control over others.

Vorelli hires a younger assistant named Grace to replace Magda and subjects her to the same hypnotic control. He uses Grace to maintain his act and extend his hold over Marianne's fate. The power of his methods grows more dangerous with each manipulation.

Vorelli visits Marianne and hypnotizes her into agreeing to marry him. He confides his plan to Spain, where he intends to transfer Marianne's spirit into another doll before letting her body die and inheriting her wealth. He opens Hugo's cage, intending to discipline Hugo for his recent rebellions.

Hugo bursts into Marianne's life through a struggle with Vorelli, and the two souls interact as the puppet and the man battle. Vorelli locks Hugo back in his cage and claims Hugo's soul is now in his body, while Marianne's hypnotized state is broken. Mark arrives as Vorelli, speaking through the voice of Hugo, begs for help while the truth of the swap becomes clear.