Lia Harris is tired of being the odd one out. She's never quite fit in with her uptight family, and now that her roommates have all found love, she's starting to feel like a third wheel in her own apartment. Fed up with her mother's constant meddling in her love life, Lia drops hints about a girlfriend she doesn't have. But with her brother's London nuptials approaching, she needs to find a date to save face. Lia turns to her best friend, Rosie, for help, and Rosie delivers--with the fun, gorgeous Grace Poston.

Grace loves to have a good time, hiding her insecurities behind a sunny smile. Her recent move to London has provided her with a much-needed fresh start. Grace isn't looking for love, and she hates weddings, having weathered more than her fair share of heartache. Friendships are different, though, so for Rosie's sake, she reluctantly agrees to pose as Lia's adoring girlfriend for the wedding festivities.

Both Grace and Lia are prepared for an awkward weekend, complete with prying family members and a guest room with only one bed. As it turns out, they get along well--spectacularly, in fact. Before they know it, the chemistry they're faking feels all too real. But is their wedding weekend a fleeting performance or the rehearsal for a love that's meant to last?