Given that the backdrop of “Gook” is an event with unavoidably political implications, it’s surprising how much of the movie seems character based and personal. The film doesn’t try to soft-pedal the racial and economic issues that exploded onto the news pages in Los Angeles in 1992, but it keeps our attention focused squarely on its key players. The story treats the consequences on a small group of racially mixed characters of the Rodney King riots, which erupted after four L.A.P.D.