The 65-year-old actor will appear alongside Maureen Lipman in next month's performance at the Old Vic theater, Britain's Sun reported Friday.
"It's all a bit of an adventure for me. But I believe there's more pure theater in a pantomime than you get in Shakespeare, and if it works, it's unforgettable," said McKellen, who starred as Gandalf in the "Lord of the Rings" film trilogy.
British theatergoers have purchased more than $1.75 million in advance tickets to the classic pantomime.
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