The Pixies mapped the expansive boundaries of their sound on 1988’s Surfer Rosa—surf music, punk, rockabilly and more—and then, with 1989’s Doolittle, they filled in the colour and made it all more accessible. Frontman Black Francis had more hooks and weirdly catchy melodies than he knew what to do with, and his lyrical concerns were by turns surreal and inscrutable. But the inherent logic and integrity of his songwriting was undeniable—each tune offered all the pleasures of pop in a noisy and aggressive package, a combination of virtues that would have huge resonance when the Pixies' influence spread through alternative rock in the '90s. Doolittle brought the Pixies a wider audience by countering every unusual turn with a moment of sweetness. “Wave of Mutilation” has a chorus worthy of a power-pop classic, but it has a deceptively complicated arrangement, with swells in volume and tricky stops and starts. “Here Comes Your Man” is the kind of song you swear you’ve known all your life when hearing it for the first time, with a twangy guitar refrain that evokes '60s bubblegum even as the lyrics are cryptic and strange. “Monkey Gone to Heaven” moves from spare verses with only bass and drums to explosive choruses, pointing to the quiet/loud structure that would become a standard form in rock within a few short years, but it’s delivered with a rare sense of urgency to match the spiritual torment of the words. Doolittle is one of the Pixies' defining albums, the ideal introduction to them and a crucial guidepost for understanding where guitar-based music was headed.