This album, a studio suite, is wrapped in mysticism. The four cards that serve as a booklet feature cabalistic signs, esoteric diagrams, a quote from Alaister Crowley and a dedication to esoteric filmmaker Kenneth Anger. A short note by John Zorn establishing a parallel between the tools and craft of musical composition and magic is the only given explanation. The aura of mystery invites an analysis of the constituents and structures of the work, for better or worse -- and in any case it's fun to do on your own, so this reviewer will not expose his personal conclusions on the subject. The musicians involved are Cyro Baptista, Jennifer Charles, Greg Cohen, Beth Hatton, Bill Laswell, Rebecca Moore, Mike Patton, Jim Pugliese, and Jamie Saft. They appear only one, two or three at a time. Each of the seven movements is based on a specific, non-reoccurring instrumentation, and explores a form of meditation, trance or anything possibly leading to spiritual revelation. "Invocation" is a delicate piece based on organ drones, while the 13-minute "Sex Magick" takes the form of a tribal percussion mantra. The piano melody in "Sacred Rites of the Left Hand Path" provides the most soothing moments and together with the first track is reminiscent of the level of writing found in Duras. "Lucifer Rising" is made of overdubbed sensual female vocals, while "Leviathan" serves up an ear-splitting slab of death metal (which can be a source of trance too, you know). "Mysteries" completes the circle with electric piano and light percussion. "Leviathan" aside, I.A.O. makes a calm, enjoyable listen and beyond its mystical claims, it includes some strong compositions.