When Omar Rodriguez-Lopez and Cedric Bixler-Zavala silenced At the Drive-In in the midst of its popular emergence, there was no question that the two artists would return with new music as exciting as their previous band. However, there was plenty of discussion in corners and over drinks about what, exactly, that music would sound like. It was clear that much more was happening under those Afros than biting, post-hardcore anthemics laced with psychedelia. In 2002, Rodriguez-Lopez and Bixler-Zavala returned with the single "Tremulant," attributed to their new project, the Mars Volta. Its shifting soundscapes were certainly a hint, but with the Mars Volta's ambitious De-Loused in the Comatorium, it's clear the ATDI expats' mushroom-headed hairstyles hide bulging brains that pulsate with ideas, influences, and a fever-pitch desire to take music forward, even if they're occasionally led too far afield for the audience to follow. A concept album of sorts, Comatorium is a swirling ten-song cycle inspired by Julio Venegas, a childhood friend of the band who followed his fearlessness to a self-inflicted end. While the storyline is bewilderingly obtuse, it nevertheless unifies the album's wildly shifting sounds. Thrumming, Led Zeppelin-inspired pounding gives way to the thump of a free jazz bass punctuated with blasts of guitar squelch in "Drunkship of Lanterns." Meanwhile, the windswept landscape of "Roulette Dares (The Haunt Of)" unfolds over seven minutes, revealing remnants of ATDI, fissures of glittering, confessional pop, and layer upon sedimentary layer of a shrieking Bixler-Zavala, harmonizing with himself over vintage 1970s organ. All of this gives way to a gentle landslide of an outro, where an expressive guitar solo that would make Carlos Santana scratch his head threads its way between brooding bass. Later, Red Hot Chili Peppers secret weapon John Frusciante stops by for "Cicatriz ESP," which undergoes a full stop after its relatively straightforward (for these guys, anyway) beginning, reentering the atmosphere to the fiery strains of at least three concurrently soloing guitarists. Though the brief-by-comparison ATDI-ish "Inertiatic ESP" acts as an opposite to the epic "Cicatriz ESP," the band's ardent desire for re-creation is defined in the latter song's shifting folds and faults. But while De-Loused in the Comatorium may well remove the stigma from the prog and art rock forms it suggests, and is certainly a monument to unbridled creativity, it can also be seen as bombastic and indulgent -- much like prog has been in the past. Comatorium is exciting, to be sure. But in a way, it avoids answering that old question about the Mars Volta: What will the music sound like?

Darren Aronofsky's second film Requiem for a Dream features a score from his Pi collaborator, former Pop Will Eat Itself vocalist/guitarist Clint Mansell. This time, Mansell blends his usual electronic/industrial leanings with brooding, evocative performances from the Kronos Quartet. As with Pi, Mansell's compositions play a large part in Requiem for a Dream, which is an adaptation of Hubert Selby's 1978 novel about the harrowing lives of four drug addicts. Impressively, Mansell's score manages to be appropriately dark and disturbing, as well as compulsively listenable.

While Stone Sour formed as an avenue from which Slipknot vocalist Corey Taylor and guitarist Jim Root could unleash their vision without upsetting the legions of Slipknot followers, it is in fact a much more impressive statement than many bands of its ilk. Those who heard "Wait and Bleed" during its radio days should be well aware that Taylor has the ability to actually sing, and on this release he does, bringing forth noticeable influences from Alice in Chains and Soundgarden. Surprisingly, Taylor is quite adept at this vocal platform, and sings with conviction, while Root plays guitar as only he can, with determined intensity. While the lyrical content shares a myriad of similarities with Slipknot, Taylor comes across as much less infuriated and this allows the songs themselves to settle smoothly, yet motivate the listener to feel the emotion being squeezed out. Many should be familiar with "Bother," which first was found on the Spider-Man soundtrack in the spring of 2002, but the songs that stand out the most are tracks like "Orchids" and "Take a Number," which strike with surprising force for an alternative rock group. The most remarkable aspect of Stone Sour's self-titled debut is how the album grows on the listener with repeat plays. Where most hard rock albums wane after too many listens, Stone Sour instead gains strength, making this an excellent album and a much more accomplished effort than Slipknot drummer Joey Jordison's Murderdolls plaything.

The sophomore effort from art house nu-metal practitioners Otep only briefly flirts with the genre's anarchic political leanings ("Warhead"), focusing instead on the medium's most revered theme: angst. The lupine howl of a shattered youth proclaiming that "I hate my life" is nothing new, so when frontwoman -- and namesake -- Otep screams the phrase endlessly throughout "Buried Alive," she's channeling everyone from post-rock mouthpieces Gordon Gano and Exene Cervenka to pop/rock tunesmiths like Roger Waters and Ricky Nelson. This would be all fine and dandy if the music contained a mere particle of the cathartic spirit of the aforementioned artists. When House of Secrets isn't pummeling the listener into submission with predictable riffs and distorted vocals, it's leading the listener into a sterile waiting room -- bereft of even the most mundane periodical -- of spoken word poetry wrapped in tedious post-Nine Inch Nails soundscapes. Otep is at her most genuine on the title cut, an atmospheric dirge that finds the artist assuming a sultry Chrissie Hynde-like croon, but it's merely a deviation from an exercise that in its entirety is mediocre at best. House of Secrets is an aggressive, brooding, dynamic, and ultimately boring offering from a band that has yet to find its own voice.