As the holidays approach, Mindy wonders if Danny is about to propose, and a case of mistaken identity leads Morgan on the perfect date.

While trying to make friends in her new city, Mindy runs into a nerd-turned-billionaire ex-flame from Princeton. She imagines the life of riches she could have had with him and questions her relationship with Danny. Meanwhile, back in New York, Danny and Morgan think they witness Lauren cheating on Jeremy with Peter, so they devise a way to spy on Peter.