Monstro is a giant whale character from Disney's animated film, Pinocchio. He is known for his massive size and fearsome appearance, often depicted with a wide-open mouth ready to swallow anything in his path. Monstro serves as a significant obstacle for Pinocchio and his father, Geppetto, who are trying to reunite after being separated. In the story, Monstro lives in the ocean and is feared by many sailors. His role highlights themes of danger and adventure, as Pinocchio and Geppetto must navigate the challenges posed by the whale to find their way back to safety.