Gary and Harry's animal magic

The secrets of filming the spectacular animal stunts in the Harry Potter film will be revealed in a TV documentary being shown tomorrow.

Hollywood animal trainer Gary Gero is the man who prepared snowy owl Gizzmo for the part of Hedwig, as well as working with cats, dog, rats and even toads for the movie.

One key moment in the film involved Hedwig swooping through the Great Hall to deliver a brand new broomstick to Harry's table. "It was our most difficult scene," said Gero, 55, who also worked on 101 Dalmatians and Dr Dolittle. "It took four or five months just to prepare."

He reveals his tricks of the trade when Rolf Harris goes behind the scenes at Leavesden Studios near Watford where they are currently filming the sequel, Harry Potter and the Chamber of Secrets. Not only is there a huge cast of 200 children, but a menagerie of furry, feathered and slimy stars. For Rolf it was "fantastic" to be able to look behind the scenes. "The work that goes into training these animals is astonishing," he said. "And it's great to see all that hard work come to fruition.

"I can't wait to see the second film, but a sneak preview with some of the animals is a great taster."

The new film will star the same Hogwarts team, with Kenneth Branagh, Maggie Smith and Robbie Coltrane. It is due out in November 2002.

BBC Animal Hospital Christmas Special, Friday 28 December, 6.30pm