In this dramatic wartime episode of This Is Your FBI, the Bureau uncovers a chilling case of espionage that begins with a single strange gesture: a Japanese prince bowing to a lowly chauffeur. But this isn’t a story of honor—it’s a story of betrayal, code words, and secret societies hiding in plain sight.

San Francisco, 1939. FBI agents witness Prince Tsuji, on an official visit from Japan, bowing to a man in a chauffeur’s uniform—an act strictly forbidden by Japan’s rigid caste system. The chauffeur, Yasu Kajioka, becomes an immediate person of interest. What follows is a patient, dangerous, and far-reaching investigation into Kajioka’s life, his influence in Japanese-American circles, and his role as a key agent of the secretive Hamushikai—a pro-Japanese organization raising funds and planning sabotage on American soil.

With the help of a brave Japanese-American university student, Tom Tanaka, who goes undercover inside Kajioka’s operation, the FBI is able to expose the inner workings of the network. Tanaka risks his life to steal and deliver a list of members, right under the noses of enemy agents during a rally staged in the basement of a Japanese high school.

But the most chilling moment comes years later—on December 7, 1941—when Pearl Harbor is bombed, and Kajioka, dressed in full military uniform, reveals his true role. He believed Japan had already won. What he didn’t know was that the FBI had been watching all along.

A suspenseful true-crime tale of patriotism, infiltration, and quiet heroism, this episode shows the high-stakes work of loyal Americans during one of the nation's most vulnerable hours.