Formulaic but entertaining, The Proposal stars Sandra Bullock as Margaret Tate, a fiery book editor who forces her young assistant, Andrew (Ryan Reynolds), to pretend they are engaged so she can avoid deportation back to her native Canada. The film, which at times is too convoluted for its own good, is a funny and appealing entry into an otherwise stale genre, thanks in large part to the likable cast, which also includes Mary Steenburgen, Craig T. Nelson and Betty White.

When The Proposal succeeds, it does so because of Reynolds’s superb comedic timing and Bullock’s mastery of physical comedy. The two stars contribute to the film’s charm, turning a potentially forgettable summer romantic comedy into one that’s funny and, at times, surprisingly poignant. Screenwriter Peter Chiarelli’s script takes full advantage of the plot’s complications and contrivances, especially during the opening 20 minutes, when Margaret and Andrew spend a weekend with Andrew’s quirky but lovable parents in Alaska in order to convince the dogged immigration officer, Mr. Gilbertson (Denis O’Hare) that their love is legit.

Later, though, the film loses some of its momentum and gets stymied by standard romantic comedy tropes. There are moments where the screenplay spins its wheels, burdening the film with a series of slapstick set-pieces that fail to elicit laughs or character insight, and unfortunately, leave the cast looking embarrassed. One sequence involves Bullock stumbling into a spiritual ceremony conducted by Andrew’s grandmother, Annie (Betty White). The sequence has Bullock and White dance to hip hop music around a campfire — it’s uncomfortable to watch and feels like another film altogether. The chemistry between the two leads is what keeps The Proposal fun and interesting, so it’s unfortunate when the director and screenwriter separate them for lengthy sequences.

Most disheartening, however, is the absence of Reynolds through much of the film’s second act. A subplot involving Andrew’s desire to win his father’s approval is established but never pays off; the same goes for another subplot involving Andrew and his ex-girlfriend, Gertrude (Malin Akerman), who he proposed to years earlier. Does Andrew still have feelings for her? The film, to its detriment, never makes it clear.

Despite a surprising amount of shots obviously filmed in front of a blue screen, director Anne Fletcher keeps the pace quick and lighthearted, avoiding the bland, plodding machinations all too common to this genre. While the ending is never in doubt, The Proposal is an enjoyable, if unsurprising, romantic comedy.