By Kim Morgan
Special to MSN Movies

If you really think about it, most movie stars (ones we truly connect with, anyway) are, in some way or another, not "matinee idol" good-looking. From Fred Astaire's elfin features to Humphrey Bogart's hound-dog face and slight lisp to Tom Hanks' guy-next-door normality to Jim Carrey's rubbery insanity, there are reasons why such characters are not relegated to merely characters. And thank goodness. How boring if all our leading men resembled Rudolph Valentino or Robert Taylor or Brad Pitt. There's plenty of room for a Steve Carell.

Which is why Seth Rogen is so wonderfully cast in Judd Apatow's acclaimed "Knocked Up," a relationship, regular-guy sex comedy that, like his previous "The 40-Year-Old Virgin," is a lot smarter than it has any right to be. Though many audiences might not recognize Rogen, the Canadian- born actor is an Apatow regular, a guy who made his mark on Apatow's excellent, insanely underwatched TV series, "Freaks and Geeks," and the director's massive hit, "The 40-Year-Old Virgin." But Rogen wasn't the lead in any of these; he never has been the lead -- until now. With his dry wit and average one-of-the-dudes qualities, Rogen seems an unlikely choice to headline "Knocked Up." Surely the studio pressured Apatow for a bigger-name star. If that was the case, thankfully Apatow stood his ground. We need to watch someone else lead a movie for a change.

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This refreshing change got us thinking about other leading men in movies who seemed unlikely. Though it's a debatable topic and requires more than one list, we're presenting seven still-working actors (some who are legendary, some who are emerging) who qualify as distinctly unconventional leads -- seven actors who we not just love but, to quote Woody Allen in "Annie Hall," in many cases "lerve." Vive la difference!

Dustin Hoffman
Can you imagine if Warren Beatty had starred in "The Graduate"? OK, the image I've conjured is pretty darn hot (Bancroft and Beatty?), but "hot" isn't entirely the point of Mike Nichols' "The Graduate." And yet, Beatty (who is obviously a major talent and would have been terrific, just different) was originally offered the famous part of Benjamin Braddock. He turned it down due to his masterful, innovative "Bonnie and Clyde" (thank goodness). And then there was hunky, rugged Robert Redford, also offered the role but reportedly deemed not right because he was too secure with his sexuality. (Imagine a nervous, sweating Redford saying, "Mrs. Robinson are you trying to seduce me?") Others were approached (including Burt Ward, AKA Robin from TV's "Batman") but it was one Dustin Hoffman, a 29-year-old stage actor, who nabbed the role of young Braddock. Clearly, the classically handsome college boy, catnip for middle-aged Mrs. Robinson, had gone in a significantly different direction. And he was perfect. Thanks, in part, to that wonderful role, Hoffman has enjoyed an award-winning, multi-faceted film career (from "Midnight Cowboy" to "Kramer vs. Kramer" to "Rain Man" to "I Heart Huckabees"), headlining movies with his distinct, dedicated talent and mischievous charm. When he walks off with the gorgeous Jessica Lange at the end of "Tootsie," you know that no matter how many times she's seen him in a dress, he's going to get the girl. Now that's some star power.

Woody Allen
Woody Allen is such an atypical leading man that one can hardly classify him in such narrow terms. And yet, he is a leading man in most of his movies: the bespectacled, ever-questioning, witty, intellectual romantic who manages to date women as beautiful and varied as Diane Keaton, Mariel Hemingway, Mia Farrow and Helena Bonham Carter. And we believe it, because brains, humor and longstanding obsessions ranging from Ingmar Bergman to Woody Herman are a lot more interesting than finely toned abdominal muscles. Woody has (quote) "gotten the girl" so much that many critics now sigh and say: enough already! But come now. Much of Allen's film career has been centered on relationships and the very passions and problems that arise between men like himself and women who could be dating Robert Redford. But the fact that the lobster simultaneously delights and frightens him in "Annie Hall," or the goombah with a gun is about to give him a helium-tainted heart attack in "Broadway Danny Rose," are part and parcel of his charm. So it's fine with me that his latest muse, the (in his words) "criminally sexy" Scarlett Johansson, who he cast in both "Match Point" and "Scoop," seems so platonically smitten with him. Though there's no romance between their characters in "Scoop," there's a sexuality that comes not only from Johansson's cinematic assets but what she says about Allen in real life. As she told New York magazine, "He has a giant brain, which he says is due to the fact that he tried to impress the girls when he was younger. But that's not true. He has a genuine thirst for knowledge. And he's a very passionate person about work and music and all kinds of things -- certainly about women." Certainly.

Next: More Unlikely Leading Men