Grayskul aren't your typical hip-hop group. They make references to The Postal Service and FernGully and rap from the perspective of the moon-landing astronauts of the Apollo 11, while still crafting Wu-Tang inspired beats and rhymes that hardest hip-hop fan can respect in songs like "Come On." Whereas their sound throughout the 2000s won them fans and collaborators like Aesop Rock, four years after their most recent album, Zenith finds the group sounding as relevant as ever, their particular sound slotting nicely along "Adult Swim"-friendly artists like Earl Sweatshirt (especially with a name like the "He-Man"-reffing Grayskul). As they say themselves, "they adapt." There's room in their world for slow rolling cloud rap ("Clubs") and Eurodance interludes ("Sleep Bounce"), but they're also socially conscious, as "Sleep Bounce" concerns the consequences of unprotected sex, and "There is No Edge," bullying and school violence. Even with a couple of high-profile guest appearances (Raekwon, Aesop Rock), Zenith stays true to its underground roots. It's an expansive release, and a welcome return from the group.