A small mouse decides to cross the world because someone asked for help. That decision costs everything. Gamba doesn't win because he's the strongest or the cleverest, he wins because he refuses to stop, and that refusal breaks something in you that expects children's adventure to stay small and safe.
An adventurous wild mouse named Gamba sets out with his friends to see the ocean. Along the way he meets a badly hurt mouse who has escaped a ship from Devil's Island, where a cruel white weasel called Noroi rules the mice through violence and terror. Gamba impulsively vows to help bring Noroi down. Made in 1984, the film is an adventure feature edited down from the 1975 TV series Gamba no Bouken, which was based on children's books by Saitou Atsuo, and it retells the main events of that series in about 90 minutes.