On this day, Aug. 20, in hip-hop history...

Columbia Records

2013: Before Odd Future's Earl Sweatshirt dropped off his debut album, he was at the center of one of the internet's great mysteries.

Three-and-a-half or so years or so beforehand, Sweatshirt, born Thebe Neruda Kgositsile to eventual UCLA law professor Cheryl Harris and renowned South African poet Keorapetse Kgositsile, had used an endlessly nimble flow, shocking subject matter and prodigious internal rhymes to earn the attention of rap fans. Then, a short while after unloading his debut mixtape, Earl, in March 2010, he vanished.

For months, fans began wondering where, exactly, Sweatshirt had gone off to and the phrase "Free Earl" became a T-Shirt, meme and the subject of countless forum threads. Then, just when it seemed that he'd never be heard from again, in 2012 he resurfaced with a tweet and a standout verse on Odd Future's The OF Tape Vol. 2.

After spending some time in Samoa's Coral Reef Academy, which was a school for at-risk youth his mother had sent him to after he'd gotten into some trouble back home, Sweatshirt was back, and the groundwork for his debut album, Doris, was set.

Checking in at 15 tracks, Doris featured an eclectic mix of production from The Neptunes, Tyler, The Creator, RZA and BadBadNotGood. It also included features from his Odd Future groupmates Tyler, Frank Ocean and OF-affiliate Vince Staples.

Thematically, Doris was a big-time departure for Earl, who traded in jokes about rape and murder for somber introspection. On "Chum," which acted as the first single from the LP, Earl serves up some details about his childhood, which was impacted when his mother and father split years prior. Peddling over a piano-driven beat, Earl gets more honest than he ever had been up to that point.

"It's probably been twelve years since my father left, left me fatherless/And I just used to say I hate him in dishonest jest/When honestly I miss this nigga, like when I was six/And every time I got the chance to say it I would swallow it/16, I'm hollow, intolerant, skip shots/I storm that whole bottle, I'll show you a role model," he raps before detailing the ways he first connected to Tyler.

Elsewhere on the LP, Sweatshirt touches on experiencing an unraveling romance ("Sunday"), the grim state of Los Angeles ("Hive") and living up to the expectations that helped make him a borderline urban legend ("Burgundy"). Whether he's discussing a flailing romance, strained familial ties or just delivering some hardbody freestyle bars ("Whoa"), Sweatshirt serves up measured observations with a healthy dose of humor, self-awareness and, of course, dense rhyme schemes and agile flows.

Earl had piqued the curiosity of rap fans everywhere, but Doris, with its mature introspection and distillation of Sweatshirt's one-of-a-kind perspective, was the moment the young phenom made good on his potential as one of the rap world's premier wordsmiths.

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