In the 10 years since she arrived in London as a know-nothing college graduate with caterpillar eyebrows and her hair in a scrunchie, American Charlotte Merryweather has transformed herself into the stylish proprietress of the city’s poshest public relations firm. Charlotte (along with her faithful assistant, Beatrice) is in pursuit of a hot new client and a home for herself and her boyfriend, when a sighting on the morning commute derails her: a curly-haired young woman in a beat-up orange VW Beetle who resembles the Charlotte of 10 years earlier. On a whim, Charlotte follows her home and discovers that, through some sort of inexplicable time-bending phenomenon, the girl is in fact Charlotte’s younger self, called Lottie. Buddying up with her doppelgänger, Charlotte finds paradoxes taking a backseat to life lessons; thinking she’s got a decade of hard-won wisdom to teach Lottie, Charlotte is surprised to find herself learning from her past persona about love, passion, and trusting herself. Though the plot mechanics grind noisily, Potter (Me and Mr. Darcy) rescues her high-concept romance with charming characters, sharp dialogue, and a satisfying conclusion.