The massive, nearly 79-minute Lateralus is TOOL entering full bloom as the 21st century's most popular, beloved, and impactful progressive rock band—a patient unfurling of heady ideas, mystical themes, and off-kilter riffs. The trademarks of their next two decades are born here on their third album—a spiral of math and science themes, brain-melting time signatures, shifting rhythmic interplay, expanding song lengths, tumbles of drums, and the metaphysical artwork of Alex Grey. It's a legacy band embarking on a new flight path, reinventing their experimental genius and finding new ways to be heavy.