Though Jackie McLean began recording as a bandleader in the '50s and established himself as a hard-bop honcho, he opened his ears to the new directions jazz was taking in the first half of the '60s. While the saxman first incorporated an avant-garde influence on 1962's Let Freedom Ring, it was One Step Beyond—released the following year—that really marked his immersion into the New Thing. One of the most immediately striking aspects of the sound is the presence of Bobby Hutcherson on vibes in place of a pianist, but that's just the edge of the avalanche. The modalism of opening track, "Saturday and Sunday," is just a warmup for what follows. "Frankenstein" and "Ghost Town," both composed by trombonist Grachan Moncur III, each combine a harmonically adventurous theme with hauntingly abstract explorations on the part of McLean, Moncur, and Hutcherson. At no point do the band delve into full-on free jazz—McLean always kept a toe in his bop-based roots—but One Step Beyond served notice that the New York sax heavyweight could be as progressive as any of the new kids on the block.