Some how for some reason, this was the last Tool album to complete my collection... Don't ask me why... I've listed to "Aenima" 4 times now, but already I find it lives up to the hype surrounding it, just like "Lateralus" did. For newcomers: This is a GREAT Tool album to start with because it contains some of the best elements of Tool: the dark, gritty and somewhat bitterly juvenile "Undertow" as well as Tool's complex though provoking magnum opus that is "Lateralus". But beware, this isn't your typical hard rock/ metal album, like other reviewers will tell you, it takes time and attention... be prepared to set aside enough time to listen to this record in it's entirety and probably not like it. You'll be rewarded though as your brain starts to sort things out and piece parts together... which is the best way I can describe it. It's just structured so differently than anything else one typically hears from popular rock groups... To be honest, I fell asleep halfway through during my second listen to "Aenima", but on the 4th listen, It hit me, and I was rockin this album just completely enthralled by it... On "Lateralus" it took me like 10+ listens to fully appreciate it, but when it finally hit me... WOW. Anyways, again, this would be an excellent place to start in my opinion... It contributed to Tool's amazing evolution. "Aenema" IS Tool's first progressive metal masterpiece.