If Joe Strummer ever gets around to writing a novel, he’ll be able to draw his characters completely from the wackos wandering through the seamy underworld of Global A Go-Go: the friend of despots and dictators who patrols pachinko parlors in “Mondo Bongo,” the paranoid activist who talks Chinese economics and blames everything on the “Gamma Ray,” the conspiracy theorist ranting through the relentless Bo Diddley beat of “Johnny Appleseed.” Strummer is a magnet for local color as he slithers around exotic playgrounds and tense urban trouble spots. He doesn’t tell stories as much as follow his chosen oddballs through their surreal routines. Naturally, he and his increasingly adept band, the Mescaleros, find the right music to complement each scene: The Caribbean political fantasia “Mondo Bongo” is set in a tranquil hotel-lounge bossa nova, while the frustration Strummer vents in the reggae blues “Cool ‘N’ Out” is reinforced by fiery, almost violent rhythm guitars. “Bhindi Bhagee,” one of several pieces utilizing hand percussion and swooping violin, finds Strummer trying to explain the sound of his band to a stranger. He hems and haws, and as the guitar careens behind him, he finally says, “There’s a bunch of players, and they’re really letting go.” That pretty much covers it.