The Magic Man is first seen after James rescues a spider from being squashed by his two cruel aunts, Spiker and Sponge, and wishes aloud that he could get as far away from this place as possible. The soldier addresses the boy by name. When James questions this, the soldier says that he knows more than just the boy's name. He then shows James a bag of magic green "crocodile tongues", which he gives to James to make his life better. The soldier describes that these magical "tongues" are "boiled in the skull of a dead witch for 20 days and 20 nights. Add the fingers of a young monkey, the gizzard of a pig, the beak of a parrot, and three spoonfuls of sugar. Stew for a week, and then let the moon do the rest". The soldier then tells James that "marvelous things will happen" if he accepts the "tongues", to which James agrees. The soldier then warns him not to lose the "crocodile tongues", or else "they'll work their magic on whoever or whatever they meet first", and disappears.
The Magic Man is last seen near the end of the movie when James arrives in New York City. After James and the giant peach are rescued from the top of the Empire State Building by the police and firemen, his aunts arrive in their beat-up car and attempt to take back James and the peach. However, the soldier who appears among the crowd of people declares aloud, "Let the boy speak!" to Spiker and Sponge.
It is also revealed in the end that the Magic Man has been narrating the story the whole time since the beginning of the film, and then winks at the viewers before the end credits start to roll.