Years of constant touring, alcoholism, and drug abuse finally began to affect Black Sabbath around the time of their fifth release, 1975's Sabotage. While it's not a bad album (in fact, it's one of their most underrated), you can sense that the magical chemistry that made such albums as Paranoid and Vol. 4 so special was beginning to disintegrate. But guitarist Tony Iommi again comes equipped with an arsenal of sturdy, ultra-heavy riffs, as evidenced by the raucous album opener, "Hole in the Sky," as well as the drug-induced anthem "Symptom of the Universe" -- both tracks coming as close to garage rock as Sabbath ever got. But the album's biggest surprise is the melodic, synth-laced "Am I Going Insane (Radio)," which is more akin to '70s power pop than to the band's patented doom metal (although the lyrics are what you'd expect -- detailing a person's downward spiral into dementia). Although often overlooked, Sabotage remains an interesting and challenging release.