Who played Gandalf in the Harry Potter movies?

Audiences know and love Ian McKellen's portrayal of Gandalf the Grey (and later White), the bearded wizard in the "Lord of the Rings" and "Hobbit" films.

But it turns out the actor could have played a hirsute magician in yet another classic film franchise: The "Harry Potter" films!

Alas, he turned the role down — and the reason may surprise you.

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"Harry Potter's" beloved Dumbledore was originally played in the franchise's first two films by Richard Harris, then by Michael Gambon for the rest of the series after Harris' death in 2002.

But Harris didn't have a very high opinion of McKellen.

During a recent interview on the BBC's "HARDTalk" show, interviewer Stephen Sackur recounted a quote in which Harris said McKellen and fellow actor Derek Jacobi were "technically brilliant but passionless."

"Nonsense," McKellen said of the criticism, noting that when Harris died he had been playing Dumbledore, but then quipped, "I played the real wizard."

Zing!

And yet, the criticism stuck. After Harris died, McKellen got a call to fill his shoes (presumably). "They called me up and said would I be interested in being in the 'Harry Potter' films," he said. "They didn't say in what part."

McKellen knew, though. "I worked out what they were thinking and I couldn't ... take over the part from an actor who I'd known didn't approve of me."

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"You mean you could've been Dumbledore?" the interviewer asked McKellen.

"Well sometimes, when I see the posters of Mike Gambon, the actor who gloriously plays Dumbledore, I think sometimes it is me," McKellen joked back.

Now, that's a magic trick!

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Ian McKellen — aka Gandalf in “The Lord of the Rings” — almost played another famed, fictional wizard as well.

McKellen was evidently approached to take over as Albus Dumbledore in “Harry Potter” when original star Richard Harris died in 2002. Harris portrayed the Headmaster of Hogwarts in the first two “Potter” pics — “Sorcerer’s Stone” and “Chamber of Secrets.”

During a recent appearance on BBC’s “HARDtalk,” interviewer Stephen Sackur brought up McKellen’s critics, recalling a remark Harris made about McKellen and fellow actors Derek Jacobi and Kenneth Branagh. Harris had said, “these guys [are] technically brilliant, but passionless.”

“Yeah,” responded McKellen. “Nonsense.”

McKellen then revealed that he received a phone call years ago about a “Harry Potter” role.

“When they called me up and said would I be interested in being in the ‘Harry Potter’ films, they didn’t say in what part,” McKellen said. “I worked out what they were thinking, and I couldn’t … I couldn’t take over the part from an actor who I’d known didn’t approve of me.”

“You mean you could’ve been Dumbledore?” Sackur asked.

“Well, sometimes, when I see the posters of Mike Gambon, the actor who gloriously plays Dumbledore, I think sometimes it is me,” McKellen replied with a laugh.

Gambon ultimately portrayed Dumbledore in the next six “Harry Potter” movies.

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Sir Ian McKellen has revealed why he never took on the role of Albus Dumbledore in the Harry Potter movies.

The 77-year-old English actor — known for playing Gandalf, another famous and bearded wizard from Lord of the Rings — said he was contacted by producers from Harry Potter to play Dumbledore, but turned down the part. His reason: Richard Harris, who played Dumbledore in the franchise before his death in 2002.

McKellen said Harris once called him a “technically brilliant, but passionless” actor — something he remembered when he was considering the role.

“I couldn’t take over the part from an actor who I’d known didn’t approve of me,” McKellen said in an interview with BBC’s HARDTalk show.

Although he declined the role, McKellen admitted that he sometimes gets confused for Michael Gambon, the actor who wound up playing Dumbledore after Harris died.

“Sometimes, when I see the posters of Mike Gambon, the actor who gloriously plays Dumbledore, I think sometimes it is me,” he joked.

Write to Mahita Gajanan at .

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