Shadowy security agencies, from the FBI to the KGB, appear in many a movie. The Japanese equivalent, the Public Security Intelligence Agency or Koan Keisatsu, similarly figures in local dramas and films, often in conflict with the regular police who regard them as secretive and uncooperative.

They also supply the title for Hiroto Hara’s mystery-thriller, “Sakura,” with the word being slang for the agency, just as “the Feds” signifies the FBI in English. Based on Yuko Yuzuki’s bestselling novel, the film has a puzzle plot typical of the genre, but its expose of Sakura’s inner workings is reminiscent of Michihito Fujii’s acclaimed 2019 thriller “The Journalist,” which ripped aside the curtain on ruling party machinations to cover up a scandal with rare realism.