By Clark Collis
January 17, 2019 at 01:48 PM EST

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The Kid Who Would Be King (out Jan. 25) stars Louis Serkis as a modern-day British lad named Alex who discovers the ancient sword Excalibur and battles the evil Morgana (Rebecca Ferguson) with help from the wizard Merlin. The latter is played, at different times, by both Angus Imrie and Jean-Luc Picard himself, Patrick Stewart.

“He was fantastic,” says the film’s writer-director Joe Cornish (Attack the Block) of the Star Trek and X-Men icon. “He was very keen not to play the conventional wizard because all his friends play wizards. [Laughs] He just hangs out with a bunch of guys that play wizards the whole time! So, his stipulation was, ‘Well, if I’m going to do this, it has to be really different.’ And luckily it was. His performance is much more down to earth and less haughty and imperious than your other wizards. It’s the first time I’d ever worked with a real big name actor, so I was a little bit nervous. But he’s terrific.”

One thing that marks Stewart’s character as different from other wizards is that his Merlin spends the movie wearing a Led Zeppelin t-shirt.

Did Cornish have to get permission from the “Stairway to Heaven” rockers for that?

“I wrote some letters to Led Zeppelin,” deadpans the filmmaker. “I wrote one to Led and one to Zeppelin.”

Watch the trailer for The Kid Who Would Be King above.

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