Matt Simon, a young advertising executive, returns to Chicago with his fiancée, Rebecca, after spending the last two years in New York. He bumps into his old friend Luke on the way into a meeting at a restaurant, in preparation for a business trip to China. Once inside, Matt thinks he overhears Lisa, the beautiful dancer he was in love with two years before, who had vanished overnight. Unable to confront the woman he believes may be Lisa, he blows off the trip and instead embarks on an obsessive search for her, as the story of Matt and Lisa's romance unfolds in flashbacks.