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In "X-Men: First Class", released in 2011, James McAvoy portrayed a young Professor Charles Xavier, before becoming the iconic leader of the X-Men. This prequel film explores Xavier's early years and delves into his complex relationship with Erik Lehnsherr, also known as Magneto. McAvoy's performance captures Xavier's journey as he grapples with his burgeoning telepathic powers while trying to prevent a nuclear war between humans and mutants.