New York City. Melvin Udall, a cranky, bigoted, obsessive-compulsive writer, finds his life turned upside down when neighboring gay artist Simon is hospitalized and his dog is entrusted to Melvin. In addition, Carol, the only waitress who will tolerate him, must leave work to care for her sick son, making it impossible for Melvin to eat breakfast.
To take down South Boston's Irish Mafia, the police send in one of their own to infiltrate the underworld, not realizing the syndicate has done likewise. While an undercover cop curries favor with the mob kingpin, a career criminal rises through the police ranks. But both sides soon discover there's a mole among them.
Corporate billionaire Edward Cole and working class mechanic Carter Chambers are worlds apart. At a crossroads in their lives, they share a hospital room and discover they have two things in common: a desire to spend the time they have left doing everything they ever wanted to do and an unrealized need to come to terms with who they are. Together they embark on the road trip of a lifetime, becoming friends along the way and learning to live life to the fullest, with insight and humor.