"The Go-Getter" is a vivid road movie, fun and full of surprising twists (with an instantly-classic rock'n'roll score by M. Ward). It's the story of Mercer White, an endearingly straight-arrow 19-year-old who, eight months after the death of his mother, steals a car and sets out to find the much older half-brother he hasn't seen in 14 years. Mercer has quite a trip.