Cee Lo’s been around for a while, right?
Almost two decades. Cee Lo Green, born Thomas Calloway, got his start in the ’90s as a rapper and frontman of the Atlanta group Goodie Mob with Big Gipp, Khujo and T-Mo. Ever heard the term “Dirty South”? It’s the title of one of the Mob’s singles, and well-named; the group was largely responsible for popularizing the rap scene in Atlanta and the South.

I thought OutKast did that.
Funny you should mention them. Goodie Mob and OutKast are both part of Dungeon Family, a collective of Atlanta artists, and Cee-Lo appears on OutKast’s “Git Up, Git Out” and “Reset.” In fact, he almost joined the group, having met André 3000 (then André Benjamin) in elementary school. Dungeon Family also recorded a collaborative album, Even in Darkness (2001). Cee-Lo appears on that one, too.

So when did he become this neo-soul man?
There’d been hints of it ever since he left Goodie Mob during the production of their 1999 album World Party. Always the most distinctive voice in the group, Cee Lo’s loopy tenor found a showcase on two solo albums, Cee-Lo Green and His Perfect Imperfections (2002) and Cee-Lo Green… Is the Soul Machine (2004). Take single Closet expand=1] Freak, which lays an unhinged Cee Lo vocal over funky horns and piano stabs and percolating, programmed beats. It’s a perfect summation of his then-meets-now appeal.

And that propelled him to fame?
Not quite yet. His solo albums, although critically acclaimed, didn’t sell much. It’s not that Cee Lo was outside the mainstream—he sang background vocals on TLC’s “Waterfalls” and co-wrote the Pussycat Dolls’ “Don’t Cha,” for instance—but his real breakthrough came after forming Gnarls Barkley with producer Danger Mouse.

Danger Mouse—where have I heard that name before?
He’s the guy who did The Grey Album (2004), a mashup of Jay-Z’s The Black Album (2003) and the Beatles’ 1968 LP The Beatles, nicknamed The White Album. EMI, which owned the rights to the latter, tried to ban Danger Mouse’s album from distribution, even though “distribution” meant a couple thousand CDs and an endless thicket of MP3s. Needless to say, it backfired. The Grey Album picked up millions of curious fans, and Danger Mouse went on to produce for Gorillaz, Sparklehorse, Beck and a slew of others.

How’d Cee Lo join that list?
Back when Danger Mouse was Brian Burton, UGA student and trip-hop hobbyist, he opened for Goodie Mob after placing second in a talent show and gave Cee-Lo a demo CD afterward. Nothing came of it at first, but they remembered each other. Their common musical taste—a shared love of Portishead, for instance—is all over Gnarls Barkley’s 2006 debut St. Elsewhere, which went platinum largely because of “Crazy.”

Hey, I’ve heard that song!
You and millions of others; it’s by far Cee Lo’s best-known and best-selling single, moving millions. Perhaps the lyrics resonated with them; not to get too topical on you, but Cee Lo’s insistence that you and he and everyone he knows are going crazy ring horrifyingly true for anyone with more than, oh, two neuroses. But credit the performances, too. “Crazy”’s moody, claustrophobic feel—inspired by spaghetti Western composer Ennio Morricone—is thanks to Danger Mouse, but the soul is all Cee-Lo.

What happened next?

Gnarls Barkley’s second album, The Odd Couple, came out in 2008, continuing their success, albeit without a hit as big as “Crazy.” Then, two years later, came a, uh, striking solo single: “Fuck expand=1] You.

Isn’t that title kind of a liability?
Actually, no. “Fuck You,” from The Lady Killer (2010), was a viral hit, went top 10 on almost every major chart and earned multiple Grammy nominations, including Song of the Year, from notoriously stuffy judges. Sure, the cursing—shown off with a cool kinetic expand=1] typography video—brought in the clicks, but the real success came from Cee Lo crooning the titular expletive like he’s reaching out to give you a bear hug. For a song about sputtering hatred, it’s remarkably welcoming. Too bad the welcome was lost on some killjoys who prompted the much-maligned radio edit “Forget You.” Considering the number of times Cee Lo sings the offending word, it’s ridiculous.

How many times?
Sixteen. Four in every chorus. That’s a Memento-worthy amount of forgetting.

Gotcha. So The Lady Killer is just a novelty album, then?
Not at all. Follow-up singles “It’s expand=1] OK” and “Bright expand=1] Lights, Bigger City” have the same appeal as “Fuck You” without the gimmickry: lush retro-soul tracks with decidedly modern takes on relationships, delivered in that impossibly cool voice. And speaking of impossibly cool voices, Cee Lo will judge yours! That is, if you’re a contestant on NBC’s upcoming American Idol rival The Voice, where he’ll be a judge with Maroon 5 frontman Adam Levine. No word on whether “Fuck You” will be an exit song.

Wait, but what happened to Goodie Mob?
Well, Cee Lo’s departure was kind of rough—Goodie Mob’s first album without him, 2004’s One Monkey Don’t Stop No Show, had a chimpanzee on the cover art in his place. Subtle. But the Mob reunited in 2009 for a concert. A reunion album is due soon, bringing Cee Lo’s career full circle.