Blues buffs have some genuine cause for rejoicing: Robert Mugge's 1991 documentary about blues performers in the Mississippi Delta, made for England's Channel Four, contains some of the best blues I've ever heard or seen on film. Using blues critic and historian Robert Palmer—accompanied by Dave Stewart (of the Eurythmics)—as tour guide, the film proceeds from a sadly gentrified Beale Street in Memphis to funky Mississippi outposts like Holly Springs, Greenville, Clarksdale, and Betonia, where we're treated to brief interviews with and extended live performances by Booker T. Laury, R.L. Burnside, Jessie Mae Hemphill, Junior Kimbrough, Roosevelt “Booba” Barnes and the Playboys, Big Jack Johnson, Jack Owens, Bud Spires, and Lonnie Pitchford. Palmer wears his erudition lightly, but he's very good on the African origins of such things as the word “juke” and the homemade blues instrument called the diddly bow. This isn't anything special as cinema, but if you're into blues it's a bonanza.