Mr. Kentaro Moto (Peter Lorre) is masquerading as an antique dealer who works as an agent of the International Police to hunt down a sinister spy leader named Fabian the Great (Ricardo Cortez). Fabian is plotting to disrupt the peaceful relationship between England and France. His plan is to blow up the French fleet while it steams through Port Said in the Suez Canal in which the incident may start a second World War. Fabian then poses as a ventriloquist in order to hide his activities. Meanwhile, Richard Burke, a British agent has already infiltrated the spy ring under the alias of Danforth (John Carradine) and at the same time warned the French about the danger. When Fabian is about to signal Eric Norvel to detonate the explosives, Mr. Moto manages to intercept Eric before the fleet reaches the port. Furious, Fabian decides to kill Mr. Moto himself but is shot by his girlfriend, Connie Porter (Virginia Field).