Film staff have had to increase security after the plastic items kept vanishing, as if by magic.
They were taken from the set of Hagrid's Hut in Glencoe, Scotland.
Cast arriving soon
Crews have been working there for weeks, sorting out a new set for Hagrid's home in the grounds of Hogwarts.
There's also a pumpkin patch, rocks and a spooky scarecrow there.
Hundreds of cast and crew are due to arrive at the spot in the Scottish Highlands next weekend, when filming starts there.
They'd better watch out though - or they might end up in Azkaban!
Hear Story
Watching filming at Leavesden
