He's nearly 70 years old but knows enough about superheroes, mutants and wizards to lay the smackdown on any cocksure comic-book geek. He makes reference to Shakespeare and Stan Lee in a single breath, thanking them both for filling his mouth with equally powerful prose. He has brought in box-office billions playing some of the most badass characters of the past decade but has never shied away from being one of the most high-profile gay actors in Hollywood.

Sir Ian McKellen has long been one of the more fascinating talents in Hollywood. And during a recent interview about the two massive blockbusters he's unleashing this month, the outspoken actor left little doubt that his personality is every bit as magnetic as his "X-Men" alter ego.

"If I'm playing the villain, I always stick up for him," said the Oscar-nominated heavyweight, who brings humanity to morally complex roles in both "X-Men 3" and "The Da Vinci Code." "That's my responsibility. ... If you don't like [my] explanation, fair enough. But there usually is an explanation of why these people do dreadful things. If there isn't a reason, you're in the business of melodrama. And I'm not interested in melodrama.

"I've played enough baddies like Richard III onscreen and Magneto and Kurt Dussander in 'Apt Pupil' or Iago onstage in 'Macbeth,' " grinned the veteran, his tranquil tone as inviting as it is disquieting. "What links them all is some passionate need inside linked with some psychological inadequacy that if you don't understand, you might foolishly dismiss — just as people have dismissed actual villains, like Hitler and Saddam Hussein, as being 'evil.' That doesn't explain a thing. The interesting thing about Hitler is not that he was evil; it's why he did dreadful things.

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"Find out why, and you'll change the world," he said. "That's what I try to do as an actor."

In May 26's "X-Men: The Last Stand," McKellen digs deeper than ever into his explanation of the "why" behind Magneto's villainous ways. The supposedly final film has the mischievous mutant seizing upon the controversy raised by a supposed "cure" for the superpowered characters and simultaneously stealing an all-powerful ally from the ranks of Professor X.

"Famke [Janssen] had to work very, very hard on this part," McKellen beamed, proud of his co-star, who explores the evolution of Jean Grey into Phoenix. "She was asked to do some almost impossible things, and I was in very close quarters and saw her do them. I think people are going to be amazed and thrilled with her performance in this, and I should think it would lead to other highly dramatic stuff as well — Joan Crawford stuff."

Welcome to the world of this one-of-a-kind pop icon, who can link the star of the clunker "I Spy" to a 30-years-deceased Oscar winner. It's his opinion, and only a fool would argue that it's an uneducated one. Once talk turns to "Da Vinci," he similarly has no shortage of heartfelt (and startling) declarations to make.

(Watch an exclusive five-minute clip from "The Da Vinci Code" on Overdrive here.)

"One of the things I liked about the book is that it did point fingers and open up question marks about very, very powerful institutions with an agenda," McKellen declared of the religious backdrop essential to the mysterious tale. "I'm an atheist. There's a lot about the Catholic Church I don't approve of, simply because they don't approve of me."

McKellen's "Da Vinci Code" character, Sir Leigh Teabing, is "an intellectual, an academic and a thinker. He's a bit of a philosopher," the actor said. "That's what comes into play when the Tom Hanks character bumps into him and starts talking about his obsession, which is the Holy Grail, and where it is, and what it is, and why it is."

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As someone who recently adapted several equally "holy" scriptures for the big screen — a.k.a. "The Lord of the Rings" — McKellen draws comparisons between the "Da Vinci" puzzle and his Gandalf glory, noting that both honored their texts without becoming slaves to them.

"You're not making the book; you're making a screenplay of the book, so it's of limited help to read the resource material," he revealed of his technique. "I found that with the Tolkien books with 'Lord of the Rings' as well. [Reading them] can be useful, but you can't suddenly come to ['Da Vinci' screenwriter] Akiva Goldsman and go: 'I found a very interesting thing in the book. Can we put this in?' He thought about that months ago."

Goldsman, along with director Ron Howard and novelist Dan Brown, have spent years navigating the religious powder keg that could sink the movie as easily as it could inspire the masses that embraced the source material. As far as McKellen is concerned, however, anyone taking the religious high ground is simply making much ado about nothing.

"The Vatican is always saying very rude and unnecessary things about gay people, so I tend to keep out of their way and not listen to what they say," he said. "I think their views on this book are understandable in that they wish it wasn't there, but it [is] there, and I think they should just shut up and let people get on with reading it and seeing the movie.

"It's basically a thriller; it's a work of fiction," he continued. "It's not aimed to bring down the Catholic Church or Opus Dei or anything else. However, it does have things to say about those institutions, and so do I, and so do a lot of people. There's nothing wrong in that. It's appropriate that people think about these things. If 'The Da Vinci Code' is part of the agency by which people do that, I'm all for it."

McKellen plans to continue balancing tiny flicks like "Gods and Monsters" with pedigreed popcorn flicks. "They're work," he sighed. Then, searching for an adjective to explain his liberal choices, a tiny grin grew in the corners of McKellen's mouth. "I've always had really catholic tastes when it comes to the work I do."

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