Celeste, a Scandinavian aristocrat who has lost everything in the war, is trained as a killer and spy by an American officer in World War II. But, years after the war, he learns that killing has become a habit with her.
An Aldermaston-type ban-the-bomb group is staging sit-in demonstrations around London, even on the steps of Whitehall. Worse, they keep releasing top secret documents in fliers and press releases, so a young agent is sent to infiltrate them to discover who their government source is.
A young American in France joins a trio of French anti-nuclear protesters in the kidnapping of Professor Moreau, an eminent scientist. But one of them has another agenda - a personal revenge on the Professor.