He performs his extended nude scene at the movie's outset - his foxy girlfriend (Kristen Bell) is dumping him, and he decides that putting on his clothes will somehow make the break-up final and official.
That's a funny idea, but the unhinged laughter emanating from the audience derives in part from the audacity/incongruity of the lumpen Segel and his not-ready-for-prime-time physique.
It was during the '90s that the transgressive comedy ran out of things to transgress, but Apatow may be onto something new here. What makes Segel's nakedness daring isn't the package, but the shabby wrapping that surrounds it.
In this age of the airbrush, of botox, steroids, HGH, personal Nazi trainers and the rampant emaciation among movie stars that advertises sit-ups and self-denial - Segel's physique is a form of rebellion.
It's also very much in keeping with his character, Peter (an apt first name) Bretter. While Sarah is away filming her TV show (seen in hilarious outtakes, it's a "CSI"-ish show with William Baldwin making mock ghoulish remarks about corpses), Peter is on the couch, procrastinating (he's a composer), eating mountains of Fruit Loops out of a wok.
He has the body that prolonged inertia can create, and it's really the inertia that sends his girlfriend packing. When she leaves, the inconsolable Peter impulsively decides to go somewhere warm for some tropical healing.
He chooses Hawaii and - small, cruel world - ends up staying in the same hotel as his ex (a coincidence the movie manages to explain) and her priapic, Euro-pop-star boyfriend (the movie is sexually candid, frequently side-splitting).
The plot finds the lovelorn Peter getting sympathy from the hotel's foxy hostess (Mila Kunis) - herself still smarting from a breakup - a pairing that sets in motion the movie's love-triangle.
