Produced but not directed by Judd Apatow, "Forgetting Sarah Marshall" features the same slyly funny, proudly R-rated brand of humor that audiences ate up in 2005's "The 40-Year-Old Virgin" and 2007's "Knocked Up." Like those two Apatow hits, too, the film is smarter and gentler than the average studio comedy, but also destined to be overrated in some circles. Walking out of the theater, the earth didn't shake, my mind wasn't blown away by some new genius masterpiece and, in a few days, its details may not remain all that memorable. Nonetheless, the core questions of any comedy must be asked. Was the movie entertaining? Yes. Did it quite consistently earn some big laughs and small chuckles? Yes. Was the audience's intelligence insulted? Thankfully, no.

When his beloved girlfriend of five years, television star Sarah Marshall (Kristen Bell), unceremoniously dumps him, sensitive music composer Peter Bretter (Jason Segel) is left shattered and heartbroken. Convinced by brother Brian (Bill Hader) that taking a vacation will help clear his mind, Peter hops a plane to Hawaii and hasn't even fully checked in when he discovers Sarah and her new beau, famous emo musician Aldous Snow (Russell Brand), are staying at the same hotel. Determined to make the most of his trip, he starts spending time with friendly hotel desk clerk Racheal (Mila Kunis), who encourages him to refocus his career goals and do what makes him happy. Avoiding Sarah and Aldous, however, soon turns out to be an impossibility.

Directed by Nicholas Stoller (writer of 2005's "Fun with Dick and Jane," making his helming debut) and written by lead actor Jason Segel, "Forgetting Sarah Marshall" unavoidably reminds of 2007's "The Heartbreak Kid," a mean-spirited turkey that also happened to be a bawdy romantic comedy set in an exotic locale. Almost by default—but also because there's actually a brain in its head—this film is far superior. The humor, which relies more on dialogue and actor witticism than over-the-top theatrics, is on-target much of the time, its only failure in this department being the forced and overdone stabs at making male nudity funny simply because a penis is onscreen. This aside, there are many amusing moments, including satirical digs at the overwrought, double-entendre-laden "CSI"-style investigation dramas and whiney musicians who take being morose too seriously. There is even a strategically vague but undeniable dig at 2006's cruddy J-horror remake of "Pulse;" the star of that film, Kristen Bell, plays an actress here whose last feature was a cruddy genre piece about killer cell phones. Bell is a good sport in this scene, and let's hope the people she worked with on "Pulse" can take a joke.

At its heart, "Forgetting Sarah Marshall" is a love story, just as "The 40-Year-Old Virgin" and "Knocked Up" were. There shall be no awards handed out for innovation in this area since it is clear who Peter is going to wind up with. While Sarah is written not as a witch but as a fairly sympathetic person, she still has enough character flaws—like the cheating she did behind Peter's back while they were still together—for the viewer to see she's not the one for him. Racheal, on the other hand, is sweet, understanding, fun-loving and believes in monogamy. In other words, she's the ideal central love interest. In his first leading man part, Jason Segel (TV's "How I Met Your Mother") is an affable sweetheart as Peter, kind of like a younger Adam Sandler without the abrasiveness, and will go to any lengths to win the audience's affections. As Racheal, Mila Kunis (TV's late "That '70s Show") is a laid-back joy who lends her character a street-wise quality, as well as a welcome humility.

By comparison to Kunis, Kristen Bell (TV's now-defunct "Veronica Mars") has a more thankless part as the title character of Sarah Marshall. Sarah is treated like a real person and not a bad guy, but she doesn't have much to do in the long run, and exits the picture near the end in an unsatisfying way. There feels like a last scene is missing with her, and the one opportunity for closure between Peter and Sarah during the finale is sorely overlooked. Bell is a big talent—bigger than this role requires.

Stealing the camera whenever he's onscreen is Russell Brand, a fascinating, little-known British actor who is an absolute stitch as Aldous Snow. Though Aldous is pretentious and sort of pompous, he is also disarmingly likable in spite of those characteristics, and Brand only adds to the character's zonky charm. Popping up in flashy supporting roles is an array of funny people, from Jonah Hill (2007's "Superbad") as a restaurant host with a crush on Aldous, to Paul Rudd (2008's "Over Her Dead Body") as a brain-fried surfer bum seemingly living on another planet, to Jack McBrayer (TV's "30 Rock") as a newlywed with troubles in the sack, to bright newcomer Liz Cackowski as Peter's brother's terminally cheerful wife.

"Forgetting Sarah Marshall" is insubstantial but ultimately gets the job done, serving up a nearly two-hour diversion that doesn't stray from the path of predictability and doesn't necessarily need to. The romance between Peter and Racheal is sweetness incarnate, the gags work more often than not, and the climax set at the opening of a "Dracula" rock opera with puppets is winning enough to become the next "Avenue Q" if someone wanted to expand what shows up in the film. "Forgetting Sarah Marshall" is light and engaging even if, to the disappointment of Kristen Bell fans the world over, Sarah Marshall is more or less forgotten by the end.