There’s a scene in Judd Apatow’s “Funny People” in which George Simmons (Adam Sandler), faced with the prospect of terminal illness, takes the stage at a comedy club and performs a morbid piano piece describing the comedy world after his death. Simmons, whose success over the years has given him little left to prove as a comedian, steps outside his usual style and gives an unsettling yet powerful performance, the authenticity of which is directly a result of the new perspective his illness has given him.

Lil Wayne’s Rebirth bears a lot of thematic resemblance to this scene, even if it is sporadically compromised by jejune passages. There has been lot of hype and speculation over the much anticipated “rock” album from the self-proclaimed best rapper alive, and in a post-808s & Heartbreak rap canon hip-hop fans have become wary of rappers stepping outside their chosen milieu for new artistic endeavors.

But Rebirth reveals an unexpectedly passionate and effusive side to Lil Wayne, eschewing drum machines and other hip-hop hallmarks in favor of more emotive rock sonics. He’s borrowing the rock genre, not attempting to conquer it.

Though the 14 tracks are structurally pro forma, Lil Wayne employs different subgenres of rock for different thematic purposes. “Ground Zero” sounds like something you’d hear during an intermission for the Blue Man Group, while “Get A Life” resembles a sped-up, rapperized Elvis Costello track, but its lyrics are as unpolished as the title suggests.

“Knockout” has a decidedly Blink-182 vibe, and on “One Way Trip,” Lil Wayne wastes no time in reminding the listener that Travis Barker has lent some veteran chops to the project. “Paradice,” with the most diverse instrumentation, is a retrospective on the duality of success and probably the album’s best track, as Wayne muses, “It’s like I have it all / But what’s it all worth… Oh no, this ain’t paradise.”

But most surprising is the genuine and awkward angst shown over women and relationships on Rebirth, which in this way is a big departure from the big pimpin’ ethos that has dominated the hip-hop genre almost since its inception. The final three songs on the album are all highly passionate takes on the opposite sex, and not the kind hip-hop fans are used to hearing.

“The Price is Wrong” is about as emo as Lil Wayne can possibly get, and on “I’ll Die Without You” he tells a mystery woman, “I love you like no other / I treat you like no other / I need you in my motherfucking life.” Rebirth ends with “I’m So Over You,” a title you would sooner expect to find on an Avril Lavigne record.

That said, Rebirth is not the apotheosis of Lil Wayne’s chosen style that Tha Carter III was, but neither is it intended to be. Fans will undoubtedly miss the frenetic style and fluidity of former hits like “A Milli” or “Let the Beat Build.”

But before we lambaste Weezy for being haplessly out of his element, it’s likely that he could make another marijuana-infused smash album if he really wanted to — he basically did with No Ceilings — and at the very least the genre mixing raises some interesting questions about hip-hop’s development and the MC imago. Lil Wayne’s latest effort should not be without its due praise, even if it is angsty at times and the visceral confidence of the Dr. Carter of yesteryear is harder to find.

2 1/2 stars out of 5.