A Japanese hip-hop musical? How about a samurai swashbuckler set on the streets of Compton, California? But Sion Sono makes his new film, "Tokyo Tribe," more than an oddity of cultural appropriation. Truth be told, I felt queasy as the story, based on a manga by Santa Inoue, began to unfold in a crime-ridden near-future Tokyo, with the "tribes" (gangs) of the title ruling the streets as the cops complicitly look on. Was this, I wondered, Sono's twisted idea of a rap paradise? Was he grossly stereotyping or was he not?