|KGB agent, Major Valeri Petrofsky has been reassigned at the request of the KGB Chairman for a secret mission, wherein he is sent to England to establish a residence near an American Military base and receive various items for couriers from the USSR. John Preston is the top British spy catcher however after a recent embarrassment he is reassigned to the menial task of overseeing airports and ports. One day one the couriers Petrofsky was expecting had an encounter with customs which left him dead. Preston then went through his things and found that he was carrying a thing that is part of an atomic bomb. Preston then suspects that someone is bringing in parts for an atomic bomb and begins trying to find this person.