Bob Harris (BILL MURRAY) is an American movie actor who's in Tokyo shooting a series of ads for a brand of Whiskey. Charlotte (SCARLETT JOHANSSON) is a recent philosophy major graduate who's also in the capital, but it's her photographer husband, John (GIOVANNI RIBISI), who's doing all of the work.
Both Bob and Charlotte aren't happy with their respective positions in life. Despite being famous and rich, Bob is going through a midlife crisis and no longer finds his marriage to his wife fun or rewarding. While Charlotte loves John, she's bored with being alone in a land where she can't understand the language, isn't sure of who or what she should or wants to be, and isn't happy that John is spending a lot of time with American actress Kelly (ANNA FARIS).
Suffering from recurring insomnia, Bob and Charlotte eventually meet and recognize that they're kindred spirits despite coming from different generations. As Bob remains in town for an appearance on a popular TV talk show, he and Charlotte soon become fast friends and explore the land while ultimately discovering that they can truly be happy.