Zappa's three-night stand at L.A.'s Roxy Theatre in 1973 was a legendary run, never documented in full until this epic, four-hour collection. His band, which included keyboard whiz George Duke and mallet percussion virtuoso Ruth Underwood, was at a peak, turning on a dime from the death-defying changes and dizzying licks of jazz fusion-oriented tunes like "Rdnzl" and "T'Mershi Duween" to the down-and-dirty vibe and caustic humour of "Cosmik Debris" and "Penguin in Bondage". And a multitude of bonus tracks from rehearsals and contemporaneous recording sessions extend the legacy even further.