Fawning filmmaker Marty Di Bergi (Rob Reiner) puts together an affectionate documentary of Spinal Tap, his favorite British heavy-metal group. Almost in spite of himself, Di Bergi turns out a revelatory study of how failure has dogged the group ever since its inception--and how the Tap has always been its own worst enemy. Highlights include the "sexism" controversy over the cover of their "Smell the Glove" album; their pathetic, money-losing attempt to emulate the Beatles with their "Black Album;" their inappropriate bookings at state fairs and company picnics; their disastrous on-stage appearances of the 1980s, wherein such props as huge plastic wombs fail to properly function; and the intrusion of a "Yoko Ono" type who all but destroys the group's shaky solidarity. Spinal Tap never really existed, of course, but in-the-know reviewers went along with Reiner's joke, treating the Tap as though they were genuine well-established rockers; the ruse persists to this day, with sellout concerts featuring the faux four. The group is portrayed by expert farceurs Michael McKean, Christopher Guest, Harry Shearer and R.J. Parnell (the first three mentioned actors also collaborated on the free-form screenplay with Reiner). The film is studded with hilarious cameos appearances by Paul Shaffer, Tony Hendra, Patrick McNee, Howard Hesseman, Paul Benedict, Ed Begley Jr., Anjelica Huston, Fran Drescher, and many others. Though a satire through-and-through, This is Spinal Tap contains more truths about the quicksilver music industry than many "straight" rockumentaries.