“Forgetting Sarah Marshall” sees a wide theatrical release next week, as does its main character’s private parts.

Under the male nudity and general grossness on the surface, this is a charming romance that manages to keep its relationships emotionally true to life.

This is the third Judd Apatow-produced movie to be released after 2007’s back-to-back knockouts “Knocked Up” and “Superbad.” Unlike “Walk Hard” and “Drillbit Taylor,” “Sarah Marshall” manages to be funny, romantic and relevant enough to deserve to be listed with those two great comedies of last year.

Jason Segel (”Knocked Up”) plays Peter, a musical composer for a hit crime procedural television show who dreams of completing the composition of his own rock opera. Peter has been dating the show’s star, Sarah Marshall (Kristin Bell of “Veronica Mars”).

When Sarah breaks up with him, the devastated Peter decides to take a Hawaiian vacation to clear his head, only to find that he is staying in the same resort as Sarah and her new rock star boyfriend Aldous (Brit comedian Russell Brand).

The main conflict of Peter being reminded of his heartbreak at every turn while simultaneously trying to move on is handled very honestly, and keeps the film clever enough to keep it from getting stale.

Things are further complicated for Peter when he becomes infatuated with Rachel (Mila Kunis of “That 70s Show”) who works at the resort’s front desk and has plenty of personal issues of her own.

The three main romantic characters of the film, Peter, Rachel and Sarah, are all very well-done. Anyone who has been in a long-term relationship that ended badly will find truth in Peter’s plight. Kunis is immediately likable as Rachel, but the film’s real triumph is its handling of Sarah, the “bad guy” of the story.

Bell and the script both work to make Sarah simultaneously antagonistic and sympathetic, and by the end of the film, the audience will feel bad for Sarah, although they are still ultimately rooting for Peter. It portrays the ambiguity and difficulty of a messy breakup with frankness and honesty.

The two big issues with this movie are its pacing and the handling of supporting characters. Especially at the beginning, the film struggles to find its tempo.

At first it lingers on Peter’s pain and loss, and then it seems to cut its losses midway through a scene to take us immediately to Hawaii. While nothing kills the movie, it certainly could have used a little more time in the editing booth.

The supporting cast, as is usual for an Apatow film, is very strong, yet director Nicholas Stoller does not seem to know what quite to do with them. Aldous, Sarah’s superstar boy-toy, teeters in between being an important character and a sidekick. He gets a proportionate amount of screen time, yet is never fully fleshed out in his own right.

Russell Brand manages to work with what he has, however, to make the character both charming and slimy, at times simultaneously.

The rest of the supporting cast has to struggle to be noticed.

The superb Paul Rudd (”Knocked Up”) plays a burnt out surfing instructor who is so superfluous that audiences may not even notice Rudd is in the film until after it is over.

On the inverse, Jonah Hill (”Superbad”) was entirely overused as a waiter. He pops up at regular intervals, like an incurable venereal disease, with the sole purpose of not being funny.

“Forgetting Sarah Marshall” is a light-hearted romantic comedy grounded in both real-world relationship conflicts and Apatowian gross-out humor. Most people will find something to like here, and although it bears some apparent flaws, it is nonetheless worth the watch.

Three stars out of five.

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