In the wake of a horrendous crime committed by his older brother, Makoto (Ryo Anraku) runs away from home and follows around a mysterious, silent vagrant (played by Katayama) who gets hired to beat people up. At the same time, radio announcer Hiromi (Mie Ota) tries to ward off the increasingly aggressive attention of her boss, with whom she starts a half-hearted affair, while struggling to find genuine love and compassion. As the different kinds of violence in both Makoto and Hiromi's lives escalate, Roar builds to a boiling point that finds the two strangers confronting the violence within themselves and their individual desire for liberation.