Pianist and composer Carla Bley’s earliest leader projects were under the auspices of the Jazz Composer’s Orchestra, a unit she cofounded in 1965 with trumpeter and then-husband Michael Mantler. Her Mantler-produced 1971 epic Escalator Over the Hill is like nothing else of the period: An abstract jazz opera with libretto by poet and lyricist Paul Haines, and a cast including giants of free improvisation, fusion, and what came to be called world music. The vocal lineup grabs one’s attention, featuring Jack Bruce (of Cream and The Tony Williams Lifetime) in one of the most prominent roles; Linda Ronstadt as the character Ginger, singing “Why” and “Doctor Why”; Don Preston (of The Mothers of Invention) on “Like Animals” and “End of Animals”; the great vocal improviser Jeanne Lee on “End of Rawalpindi”; the exploratory bebop-rooted virtuoso Sheila Jordan on “Holiday in Risk”; and even Bley and Mantler’s then four-year-old daughter, Karen Mantler, on the title track. (The kid, growing up fast, returned to sing “Funnybird Song” on the smaller-scale 1974 follow-up Tropic Appetites, another work with Haines.) Five different lineups are heard in this “chronotransduction,” as Bley and Haines termed it, including the Hotel Lobby Band, Jack’s Traveling Band, the Desert Band, the Original Hotel Amateur Band, and a trio playing “Phantom Music.” The orchestration is texturally rich and ever-changing, with soloists including the Argentinian tenor shredder Gato Barbieri; violinist and AACM visionary Leroy Jenkins; guitar hero John McLaughlin (of Miles Davis and the Mahavishnu Orchestra) destroying on “Rawalpindi Blues”; trumpeter Don Cherry (of Ornette Coleman fame) on “A.I.R. All India Radio”; Italian trumpet master Enrico Rava; and the iconic rhythm partners Charlie Haden and Paul Motian on bass and drums—with Motian doubling on the Egyptian dumbek, or goblet drum. The quasi-burlesque, absurdist atmosphere of the piece doesn’t take away from its beauty. Escalator Over the Hill did much to establish Bley as a unique and prescient voice in American music.