ith a line-up of successful comedies – “40-Year-Old Virgin,” “Knocked Up,” “Superbad” – writer/director Judd Apatow and his circle of collaborators and friends seem to have nearly monopolized movie comedies in the past three years. When the wacky trailers for “Forgetting Sarah Marshall,” the new comedy produced by Apatow and written by actor Jason Segel, first surfaced on the Web, there was concern that he had spread himself too thin too quickly, and that his stamp of approval was already becoming devalued. But the highly-structured Apatow formula hasn't curdled just yet.

There’s some sad, sweet - dare we say - depth to the movie.

While it never reaches the peaks of “Knocked Up” or “Superbad,” FSM is a consistently hilarious hybrid between romantic-comedy formula and the offbeat, witty, bawdy humor that is yet again based on Apatow's own relationship experience. Under the direction of first-timer Nicholas Stoller, another collaborator from Apatow's undeclared days, Segel stars as typical Apatow-ian slob Peter Bretter, a struggling musician who does scores for a “CSI”-type show called “Crime Scene: Scene of the Crime," and his attempts to get over his ex, Sarah Marshall (Kristen Bell), the show's gorgeous star.

Right off the bat, Sarah breaks up with Peter - while he’s naked. It takes but five minutes for Segel to showcase his drooping member, setting the tone for the movie’s fearless brand of comedy. See, she won’t actually break up with him until he puts on some clothes, and so…he doesn’t. And Segal is curiously determined that his member is seen by all (he's naked again at the end of the movie). The scene is intended for big, pathos-tinged laughs. Ha ha. But, stick around; there’s also some sad, sweet - dare we say - depth to the movie.

Depressed, Peter decides to stop moping about, listening to "Nothing Compares to U," and take a little vacation at a Hawaii resort for a necessary escape, and also to complete his great opus: a dark, Gothic "Dracula" rock opera with vampire puppets. Unfortunately, he finds Sarah and her new rock star boyfriend (British comic Russell Brand in a breakout performance, though he may not have been acting) at the same resort. The resulting love triangle finds Peter torn between his desire to win Sarah back or accepting the advances of the woman who puts him back together: Rachel Jansen (Mila Kunis), a receptionist at the Hawaii hotel who sympathizes with Peter's situation and offers a supportive hand. In the interim, he has numerous amusing interactions with his goofy step-brother (Bill Hader), a stoner surf instructor (Rudd) and a wannabe rockstar waiter (Hill).

And that’s about it. From its genitally-obsessed dialogue to its tender heart, Forgetting Sarah Marshall could be pegged as yet another Apatow tale of stunted adolescence, but it is absurdly overlong and not everything works; Apatow regular Jonah Hill, for one, is irritating as an adoring Aldous Snow fan. Also, the ongoing jokes were oddly episodic. But, there's a never-a-dull-moment pace to these sexy, raunchy – and occasionally utterly pathetic - sexcapades that just keeps the surprises coming.