What happens at the end of a romantic comedy? After the whirlwind romance and the big proposal, do the characters live happily ever after? Not so, says 'I Give It a Year,' a British flick that seeks to flip the rom-com formula on its head.

Nat (Rose Byrne) and Josh (Rafe Spall) are a newly married couple who wed after only seven months of courtship. Their friends and family know they aren't right for each other: Nat is tightly wound and proper, while Josh is a regressive man-child, the kind you might find in a Judd Apatow film. In the nine months that follow, the pair quickly realize that something just isn't clicking -- they are fond of each other, but they lack the chemistry necessary to sustain the relationship, and being British, both of them are too polite to end it.

What starts out as seemingly typical rom-com fare evolves into something sharper, with a little bite courtesy of writer/director Dan Mazer, who wrote screenplays for Sacha Baron Cohen's 'Bruno' and 'Borat' movies. And the involvement of Stephen Merchant as Josh's oblivious and obnoxious friend certainly informs the audience that this isn't your typical touchy-feely flick. Byrne and Spall are equally game for hilarious comic hijinks -- Byrne in particular is continuing to show off her comedic chops following the success of 'Bridesmaids,' and it's nice to see her flex those muscles yet again, albeit in a similar, snobby role.

'I Give It a Year' also stars Anna Faris and Simon Baker as the romantic bait luring our main couple away from each other and helping them realize that there are other, more compatible people out there for them. Faris gives a more restrained performance than her usual fare, which suits her well, though she isn't completely removed from wackiness, as evidenced by one of the most cringe-inducing and awkward threesome scenes ever filmed (unless you count home video, as I'm sure there are much more cringe-inducing and awkward threesome scenes lurking in the closets of wannabe adventurous couples). The peripheral characters are also delightfully wacky, like Minnie Driver's cynical sister-in-law, who is constantly belittling her husband and fantasizes about sex with much younger men -- and it provides the opportunity for a typically serious Driver to exclaim, "I would ruin [Justin] Bieber!"

The film, while elevated by crude, biting humor and a solid cast, isn't all chuckles though. 'I Give It a Year' is a fine exploration of the way people rush to commit to one another without getting to know each other first. It also highlights the ways in which couples often stay together because they don't want to hurt each other. So often in romantic comedies we have clear protagonists and antagonists -- a nice, good-hearted woman and the man who cheats on her and breaks her heart, or the do-gooder guy and the woman who beats his heart to a pulp -- but in 'I Give It a Year' there are only shades of gray because Mazer is aware that people are complex. Nat seems more inclined to break Josh's heart than the other way around, but Josh is just as capable of making mistakes and using bad judgment as she is.

It's a bit of a mainstream comedy, sure, and for that it sometimes feels slight or conventionally paced, but it's packed with more heart and perception than most, and it treats its characters as fully realized people rather than one-dimensional sentiments dressed in human clothes.

Rating Meter 7

'Give It a Year' premiered in the US at the 2013 SXSW Film Festival. 

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