Speed Racer (Japanese 三船剛; Mifune Gō) is the main character of the serialized in print in Shueisha's 1966 Shōnen Book of the same name, and also as such, the main character of the 2008 live-action Warner Bros. film adaptation. He is known for his love of racing and valuing his family. He drives the Mach 5 (as well as other cars, such as the Mach 6 in the movie) and always manages to wind up in extreme danger with either his younger brother or his girlfriend Trixie. Speed is shown to miss his older brother, Rex Racer (secretly known as the Racer X), in both versions. He is portrayed by actor Emile Hirsch in the 2008 film.
Off the track, he wears a blue shirt with an orange "G" (standing for his Japanese first name, Gō) with a white collar, a red racing bandanna around his neck, white pants, red socks, brown loafers and yellow gloves. He is 18 years old, has a brown, almost black, pompadour, and his eyes are brown (in the anime version they are blue). In racing, he sports a white open-face helmet with an M (representing Mifune Motors) on top. In the anime, on special occasions, Speed wears a red blazer with a yellow "G" embroidered on it. In the live action film, he wears a white leather racing jacket unzipped over his classic outfit. He wears his classic outfit (without the embroidered "G") in the first half of the Casa Cristo 5000. To strengthen character back-story continuity between Speed and his older brother Rex, Speed's red socks were considered "lucky socks."