Carroll Baker plays a dual role as translator Julie Harrison and her twin sister Mary. The serpentine plot begins as Julie tells her lawyer Dave Barton that Mary's life is being threatened in London while Julie herself is being stalked by a mysterious stranger in Amsterdam.
Franco and Ciccio, two journalists, are sent to Amsterdam to investigate a mysterious murder. After having managed to infiltrate the libertine circles of the city, the two take a compromising photo that will get them into trouble.
The son of Django searches for the murderer of his father and is thereby involved in a war between two factions headed by former acquaintances of his famous parent.
