Recently divorced 41-year-old Toby Fleishman dives into the brave new world of app-based dating with the kind of success he never had dating in his youth, before he got married at the tail end of medical school. But just at the start of his first summer of sexual freedom, his ex-wife Rachel disappears leaving him with 11-year-old Hannah and 9-year-old Solly and no hint of where she is or whether she plans to return. As he balances parenting, the return of old friends Libby and Seth, a potential promotion at the hospital that is a long time coming, and all the eligible women that Manhattan has to offer, he realizes that he'll never be able to figure out what happened to Rachel until he can finally face what happened to their marriage in the first place.