In "The Usual Suspects", Roger "Verbal" Kint (Kevin Spacey), a con artist with cerebral palsy, states that Keyser Söze (Scott B. Morgan) is believed to be of Turkish origin, but some said, "He was half German through his father." Officially, Söze's nationality is publicly recorded as Turkish in the film.

According to Kint, Söze is a criminal who began his career as a small-time drug dealer. Horrifically though, one afternoon while Söze is away from his home rival Hungarian gangsters attempt to intimidate him by taking his family hostage, raping his wife, and slitting the throat of one of his children right before his eyes once he returned home. Determined to show these vicious criminals what toughness really means, Söze shoots and kills his own family and all but one of the Hungarians, letting the last leave so he can tell his cohorts what happened. After his family is buried, Söze massacres the Hungarian Mafia, their families, their friends, and people who owe them money. He goes underground, never again doing business in person, operating instead through oblivious underlings.

Söze's ruthlessness becomes legendary. Kint notes for others that Söze had enemies and disloyal henchmen brutally murdered, along with everyone they held dear, for very slight infractions. Over the years, this astute man and his criminal empire flourishes, as does his larger-than-life legend.

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