Prince William, Kate and Prince Harry toured Warner Bros. Studios Leavesden near London, home to the newly launched Making of "Harry Potter" studio tour.
There, the royals, accompanied by 500 children and adults from charities they support, got a wand lesson, visited the Hogwarts Great Hall and saw props, costumes and models from the Potter series as well as some other movies.
"Where's my brother, why isn't he doing this?" William, brandishing a wooden wand, said during the lesson.
As Kate (who also had a wand, and wore a cream-colored dress with black spots from TopShop) and William giggled, they were given some "spell techniques' by tour guide Scott Heron, then asked to face a group of children called "Dumbledore's Army" – to whom William bellowed, "Expelliarmos!"
William also seemed particularly taken with props from The Dark Knight Batman trilogy. "I'm a very happy man," he quipped after exploring those life-size props.
"To be honest, I'm over the moon just to have seen the real Batmobile and Batpod – Josh, Barry, you don't do baby seats for those cars, do you, by any chance?" William added. "On the other hand Harry's just excited to see a real-life talking owl in the Harry Potter studios. I haven't told him yet that Harry Potter is fictional, so please keep the secret for a little longer."
Friday marks the studio's official opening, although it has already been used for films including All You Need is Kill with Tom Cruise.
Additional reporting by ASSOCIATED PRESS
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