Drums thunderously cascade as opening credits roll. The film opens on cantankerous septuagenarian Ginger Baker—one of the greatest drummers ever—arguing outside of his South African compound with director Jay Bulger about allowing certain people into "his film." The squabble escalates until Baker threatens, "I'm gonna fucking put you in hospital!" Then he jabs his metal cane into Bulger's nose. The incident gets reprised near the film's end, with Bulger gradually zooming in on his cut as if it were a war injury—which, in a sense, it is.

Beware of Mr. Baker traces the itinerant sticksman's tumultuous personal and professional life from his violent childhood and loss of his father in World War II to his current status as a financially shaky, bitter Englishman abroad. In between, we get interviews with his mother, four wives, three children, siblings, bandmates, managers, a roll call of stellar drummers, and, of course, Baker. Now terminally morose but caustically funny, his scowling visage deeply lined after decades of chain-smoking, Baker spends the film in shades, belligerently answering Bulger's earnest questions. Two memorable lines: "The birth of heavy metal should've been aborted" and "I love disasters." Baker's prodigious knack for alienating nearly everyone he encounters and losing money attests to this. His life unspools in a thrilling mix of spectacular highs and lows.

Bulger follows Baker's crazy-quilt musical journey, which began with a love of American jazzers Art Blakey and Max Roach, and intensified after drummer Phil Seamen turned him on to African rhythms—and heroin. Archival footage of Baker in action—all crimson locks, mad eyes, and pistoning skinny limbs—displays his legendary technique. The movie is worth it for these passages alone. No matter if it's with Graham Bond Organisation, Cream, Blind Faith, Fela Kuti, or his own jazz combo playing at the polo grounds (he was an enthusiast), Baker always looked happiest when beating skins. Never able to stay in one place or in one band for very long, Baker left a trail of emotional devastation among those closest to him—and a legacy of flamboyant musical genius that almost makes up for his malignant behavior. Bulger's fast-paced, cancerous-warts-and-all documentary is as fascinating as one of his antihero's mind- boggling solos.