The Mars Volta has steadily built steam since debuting in 2003. The title of its fifth studio album, Octahedron, refers to an eight-sided geometric shape and the full-length features eight epic tracks that characteristically hold unexpected twists, turns, and tempo shifts. As usual, Omar Rodriguez-Lopez is credited with writing the music, Cedric Bixler Zavala is responsible for the lyrics and vocals, and a host of members comprise the larger band (including John Frusciante of Red Hot Chili Peppers). About five minutes into the gradually evolving opener, “Since We’ve Been Wrong,” snare-heavy drums join the fold and then pick up the pace on “Teflon,” where reverb-drenched guitars kick in and Zavala’s slightly sinister vocals deliver wounded, seething sentiments. Following a funky, head-bang-inducing “Cotopaxi,” the “Copernicus” ballad walks down a seven-minute path where listeners briefly encounter electronica-esque instrumentation. The theatrical cauldron continues to fester until concluding with “Luciforms” — with Zavala sounding as vengeful as ever throughout the apocalyptic journey.