Personal trainer Rebecca McCall is furious when her coworker is sidelined and she's forced to teach the “Be Your Best Bride” class. As if being a size two for your wedding photos is all for which exercise is good. Could the whole thing get more vain and sexist?

The class is full of preening, giggling bridezillas, but one woman stands out: the one who confesses she's only there because her fiancée signed her up. Who does that to someone about whom they care? And why can't Rebecca take her eyes off her?

Spencer Thompson is a second-guesser. After making the worst mistake of her life, she's happy to abdicate responsibility and let other people make her decisions for her. She's always felt a little bit too soft, a little bit too curvy in all the wrong places. Her fiancée apparently agrees because she signed Spencer up for a class at the gym.

Terrified by the online profile of the instructor, the epitome of zero body fat, Spencer is relieved to find someone new, and realistic-looking, leading the class. Except the instructor seems to hate her, and Spencer has no idea why.

When a perfectly innocent post-workout smoothie leads to an earth-shattering kiss, Rebecca wonders if she's been wrong all along, and Spencer is challenged to make another decision that could change her life forever.