Daniel Radcliffe, Emma Watson and Rupert Grint were played by small adults in wigs in Harry Potter and the Philosopher’s Stone.
Alan Rickman, who starred as Severus Snape in the films based on the books by JK Rowling, explained that child labour laws put restrictions on the filming of the early movies, meaning the young actors were replaced by “very small adults” for parts of the film.
The actor described the early days of filming as an “organisational nightmare”.
Speaking at a Bafta celebration of his work, Alan said: “In the first film, if anybody wants to look, you have the problem of kids who can only work a certain number of hours. Sometimes there were 300 children on set, and at certain points they all had to go off and do some schoolwork.”
Alan said that the trio filmed their side of conversations with the older cast members, but were replaced by little adults “with a wig on their heads” when the likes of himself and Dame Maggie Smith delivered their lines.