Directed by Roger Kumble (2002's "The Sweetest Thing"), "Just Friends" begins with a promising idea—a ridiculed, once-chubby teenage boy in love with his beautiful best friend runs into her ten years after high school graduation and discovers his feelings for her are still very much alive—but then wastes it by dodging the truth of the situation and going for stereotypes, dumb humor, and needlessly protracted plot complications. Such a premise is ripe for a lot of potent comedic potential mixed with the very real pains of adolescent memories, but Kumble never raises the characters and their relationships above one dimension. Because of this, the central romance isn't nearly as swoon-worthy as it should be, and what surrounds it hits too many false notes for comfort.

After a nightmarish post-graduation party in 1995 in which his confessions of love for best buddy Jamie (Amy Smart) were read aloud for his classmates to hear—and then Jamie worsened the experience by telling him she loved him like a brother—Chris (Ryan Reynolds) escaped from his New Jersey hometown for the West Coast, dropped a hundred pounds, and turned himself into a successful record company executive with more women than he knew what to do with.

While escorting talent-free, semi-psychotic pop-star-in-the-making Samantha James (Anna Faris) to Paris for the holidays, a freak accident onboard their private plane leads to an unscheduled landing near his old home in New Jersey. Stranded there for a day, Chris, with Samantha in tow, returns to stay with his daffily loving mom (Julie Hagerty) and sex-crazed 18-year-old brother, Mike (Christopher Marquette). While out for a night on the town, Chris unexpectedly comes into contact with Jamie for the first time in ten years. Bartending and staying with her own parents while she works on getting her teaching certificate, Jamie is presently single and blown away by seeing Chris again for the first time in ten years. As his 24-hour detour turns into several days, Chris is determined to finally win Jamie over. What he doesn't expect is that, though now a slimmed-down big shot, when it comes to finally professing his undying love for her, he is still filled with the same insecurities and lack of confidence as he always has.

An ill-advised romantic comedy that plays things way too broadly to earn its predictable, heartfelt conclusion, "Just Friends" little by little irks on the viewer's nerves because the screenplay, by Adam 'Tex' Davis, is a mess. Chris should be the quintessential, lovable underdog of the story—an unlikely hero that you want to see prevail over adversity and get the girl—but he, like most of the supporting characters, is too meanspirited and immature in his actions to care about. Granted, Chris' newfound smugness is simply a means to an end of him ultimately righting the wrongs he has made during his quest to make Jamie fall for him, but his epiphany arrives so late in the proceedings that it is difficult to muster up much sympathy for him. Jamie and Chris may have been perfect for each other back in high school, but now, a decade later, the sweet-natured, kind-hearted Jamie is too good for the childish, pushy, somewhat egotistical personality Chris displays. Other characters, like Chris' cruel, abusive younger brother, Mike, and a fellow high school nerd-turned-heartless-player, Dusty (Chris Klein), are written even more haphazardly. In the world of Adam 'Tex' Davis' script, people fall under the "good guy" or the "bad guy" category, and there is no room for anyone in between. Because of this, there is little resemblance to real people, only caricatures.

There are funny moments in "Just Friends"—a few even hilarious—but the majority of jokes try so hard and go so far over-the-top that they splat on the ground before takeoff. An impromptu ice hockey game with Chris, Jamie, and a bunch of kids that grows heated when Chris has trouble skating in his rentals, has potential that director Roger Kumble doesn't know what to do with. It isn't funny, either, to witness a front yard full of Christmas decorations get destroyed when the scene lacks a punchline, yet the viewer is supposed to find it humorous for no other reason. And when pop diva Samantha finds herself trying to perform in front of a club of metalheads, endless comic possibilities abound that are woefully squandered.

Ryan Reynolds (2005's "Waiting..."), an almost consistently amiable young actor with solid comic timing, is peculiarly off his game as Chris. There is a detachment between the viewer and the movie's protagonist that causes major trouble in being able to identify with him, and it doesn't help that he does so many hair-brained things that make him all the more hard to care about. There is a vacancy of warmth and earnestness in Reynolds' performance that dooms the romance between himself and Amy Smart (2004's "The Butterfly Effect"), lovely as Jamie. Smart's character is the only one written with any human authenticity, and the actress does wonders in making her accessible to the audience in a way that Chris never is.

The standout performance, though, is Anna Faris (2003's "Scary Movie 3"), deliciously off-kilter as she sends up any number of cutesy bubblegum pop starlets. Faris gets almost all of the film's big laughs, from her intentionally terrible singing to asinine lyrics, to her toothpaste-obsessed charades while on Vicodin, to any number of priceless facial expressions and expert line deliveries. Samantha is possibly the picture's biggest stereotype of all, and yet Faris somehow makes her adorably air-headed rather than just cruelly psychotic. Simpson sisters Jessica and Ashlee won't like the direct skewering they receive in the script, but Faris plays the part all in good fun and steals the show away from the main storyline between Chris and Jamie.

The isolated serious or low-key moments in "Just Friends" that don't go the way of slapstick and concentrate on who Jamie and Chris were as teenagers, and who they have become, show nice signs of a good film screaming to get out of the Idiot Plot they have found themselves in. Alas, they are few and far between, virtually lost amidst one cliche and one frustrating misunderstanding after another. For instance, there is not one, but two separate soul-bearing climactic sequences that play out in front of audiences—one at a church, another at a bar—stripping them of any honesty they might have had because of it. When the time comes for Chris and Jamie to finally reunite, the outcome is emotionally cold; prior to this, they have said some terrible things to each other in the heat of an argument so vicious that they overshadow the supposed feel-good conclusion. Maybe "Just Friends" is all these two should have remained; as lovers, they'll probably be miserable.