"The Proposal" involves coercion, fraud, scheming, deception, and two night-and-day types who can't help but start to feel guilty about their knowing betrayal. Oh, yeah, it's also a romantic comedy. Considering that the plot is gimmicky and exceedingly predictable, built upon the type of simplistic, easily marketable logline mainstream Hollywood loves, it is something of a miracle how appealing the film proper is. Director Anne Fletcher (2008's "28 Dresses") and first-time screenwriter Peter Chiarelli have concocted a bouncy, lightweight charmer, albeit one that has been seen countless times before, and they are further blessed with the amiable likes of Sandra Bullock (2007's "Premonition") and Ryan Reynolds (2009's "Adventureland") in the lead roles. "The Proposal" ultimately surpasses the viewer's cautious expectations for about eighty minutes, at which point the material takes an abrupt nosedive and keeps going south for the remainder of the running time. Good will can only last so long, and the third act does nothing but frustrate as trite condescension sets in.

Margaret Tate (Sandra Bullock) is the no-nonsense senior editor at NYC publishing house Colden Books, so hardened and unforgiving that even her long-suffering assistant, Andrew Paxton (Ryan Reynolds), has secretly nicknamed her "Satan's mistress." When the Canadian-born Margaret is informed that, due to a past trip outside the U.S., her Visa application has been denied and she must leave the country immediately, she suddenly risks losing her job and everything she has worked for. Desperate to find a way to be able to legally stay put, Margaret bogusly announces that she and Andrew are engaged to be married. Andrew goes along with the ruse after some return blackmailing of his own—he wants to be promoted to editor status, and have his manuscript published—but faces criminal charges if immigration officer Mr. Gilbertson (Denis O'Hare) discovers the truth. Now, with Andrew's grandmother's (Betty White) 90th birthday about to be celebrated in his hometown of Sitka, Alaska, Margaret has no choice but to accompany him for the long weekend and pull the wool over the eyes of his family and friends, including parents Grace (Mary Steenburgen) and Joe (Craig T. Nelson).

"The Proposal" opens with a fairly accurate portrayal of the book publishing business and then segues into an unoriginal story setup that fortunately features some quick wit. En route to Alaska and quizzing each other on background information, Margaret asks Andrew what she is allergic to, to which he responds, "Pine nuts and the full spectrum of human emotions." For a character as insufferable as Margaret initially is, it helps that the person playing her is so darn likable. Sandra Bullock is a delight as Margaret Tate, playing her cold side with a twinkle of humanity and then softening as the weekend with Andrew and his family commences. Parentless herself and all alone, Margaret is reminded just what it feels like to have people in your life who love and care about you, and the changes she goes through as her grinchy heart grows in size are affectingly portrayed.

Bullock and co-star Ryan Reynolds, as disarming as ever as Andrew, play off each other with a real zing and zeal. Whether bickering, sharing a nighttime heart-to-heart with the closed blinds blocking out the 24-hour Alaskan sun, or accidentally toppling into each other while wearing not a stitch of clothing, these two actors are nothing short of charismatic. The burgeoning romance between them, alas, is prolonged to such an extent that they barely have any time at all to build upon their complicated relationship before the painful confessions and heartfelt declarations of the climax get underway. In their place are a handful of uneven comic bits—a scene involving a cell phone, an eagle, and the Paxton's beloved little dog is riotous, while another scene involving the only male stripper in Sitka is uncomfortable and not exactly clear on why the viewer should find it humorous—interspersed with dramatic conflict involving Joe's desire for the uninterested Andrew to carry on the family business and Margaret's shame over lying to Andrew's warm family.

As Grandma Annie, the iconic Betty White (2003's "Bringing Down the House") is as funny and genuine as always, receiving one of the juiciest film roles of her predominately small-screen career. If for nothing else, credit screenwriter Peter Chiarelli for writing a part for an elderly person that isn't used as just a punchline, and also for treating Andrew's former girlfriend, Gertrude (Malin Akerman), with a kindness and believability rather than as a stereotype or shrew. In supporting performances, Malin Akerman (2009's "Watchmen") does well with her understated turn, and Mary Steenburgen (2008's "Step Brothers") and Craig T. Nelson (2005's "The Family Stone") are equally fine as Andrew's parents, Grace and Joe.

There comes a point near the conclusion of "The Proposal" where an ending could have arrived that was simple, honest, and impactful without a word needing to be uttered. Director Anne Fletcher does not consider it, instead choosing to journey down an avenue so formulaic the viewer's heart shatters at the very realization of it. A scene where a character apologizes to a barn filled with wedding guests is bad enough, as is a later mad dash to the airport, but the last scene is worst of all. Cloying beyond belief, this denouement sacrifices the true emotions that have grown between Margaret and Andrew in exchange for unforgivable, cutesy, meddlesome cut-away shots of nosey coworkers fawning over the love story happening before their eyes. Outside of the slow clap (which can work in rare instances), there is no feel-good cinematic cliché more dishonest and sickeningly manipulative than that of extras reacting to the uniting of romantic leads. "The Proposal" was never going to be considered original, but it at least appeared to be smarter than what the disappointing final twenty minutes offer. Promising though it is for so long, the film culminates in discouraging, run-of-the-mill developments that treat the audience with a contempt of the genre's lowest-common-denominator.