For as long as Madeleine Mad Rousseau can remember, shes been the sweet twin to her sister Jaxs sassy. But after an especially painful break-up, Mad decides shes had enough of being sweet. Childrens librarian during the day, she begins visiting Phillys seedier nightspots on a quest for adventure and experience. When Cortlandt Cort Ambler, the ex-boyfriend of Mads sister, Jax, saves her from disaster on one such evening, an unlikely friendship is born between the rebellious librarian and the moonlighting pianistand two broken hearts begin a journey toward being whole again.