Like so many comedic actors, Seth Rogen seems to have a type. He's the lovable schlub, the agreeable, pot-smoking best friend who avoids conflict until absolutely necessary. It's easy to watch him in a handful of his biggest hits, peg him as a funny, one-trick pony and move on. But, you'd be making a big mistake.

Sure, Rogen has a default persona, but his career is not defined by his popular image. Rather, his career is defined in the fringes and in the subtleties, where he takes what's expected of him and delivers something completely different. Rogen's greatest trick is that he's quietly become the most important person working in film comedy today, all without calling attention to his accomplishments.

Although he got his start on the beloved (and quickly cancelled) 'Freaks and Geeks,' Rogen rose to stardom playing lovable, overgrown man-children in films like 'The 40-Year-Old Virgin' and 'Knocked Up.' He was an ideal match for writer/director Judd Apatow's influential, improvisational style, capable of riffing with the likes of Steve Carell and Paul Rudd while injecting humanity and sweetness into his raunchy dialogue. The impact Apatow's films have had on comedy as a whole cannot be overstated -- virtually every modern funny person has a connection to or was directly inspired by this crew. You can thank (or blame) these guys for every big-hearted R-rated comedy to hit theaters in the past decade. They set a new standard and everyone rushed to copy it.

And, this is where Rogen stops being a member of a powerful trend and starts carving his own path. While Jason Segel vanished into eight seasons of 'How I Met Your Mother,' Rogen kept working and kept trying new things. In between voiceover gigs and cameos in countless other comedies, he co-wrote (with writing partner Evan Goldberg) and co-starred in 'Superbad.' Although the film certainly contains Apatow's specific comedic DNA, the youthful, whimsical tone reflect a different voice. 'Knocked Up' is a film written by a man with years of painful life experience -- 'Superbad' is a film written by two guys who are still struggling with the fact that they've been forced to grow up. It's still raunchy and bittersweet, but it's proof that Rogen was willing to explore different territory, ceding the lead roles over to younger actors (while writing a memorable supporting turn for himself, of course).

Too many comics refuse to change, Rogen feels like he's just getting started.

You see this generosity as an actor and filmmaker in future projects, too. In 'Pineapple Express,' he turns his typical stoner character on his head, making him a working professional with an illegal vice instead of the layabout stoner. It's one of his most straightforward and deadpan roles, giving him the difficult task of playing straight-man to the more absurd characters portrayed by James Franco and Danny McBride. Franco and McBride get the best lines and the most memorable moments, but they wouldn't work without Rogen's pitch-perfect reactions. Few actors can escalate from a serene calm into sheer panic as effectively as Rogen and he's used to to great effect throughout his career to make everyone around him funnier.

Rogen often seems content to gel as part of a perfectly built ensemble, but his choices in more central roles couldn't be eclectic or brave. In the massively underrated modern gem 'Observe and Report,' he finally makes proper use of his imposing figure. His sociopathic mall security guard is still an overgrown baby, but he's far from harmless. Channeling the likes of Travis Bickle, Rogen throws caution to wind and creates a comedic hero so brutally unlikable that the films dares you to remotely sympathize with him. For a guy who built his name on playing the goofy best friend, it's a brave role that pays off beautifully. 'Observe and Report' was a box office bomb, but it showcases an actor willing to step far outside of his comfort zone without hesitation. With so many modern comics playing it safe with every film they make, Rogen's choices are just plain refreshing.

As the slightly broken moral compass at the center of 'Funny People,' he essentially plays himself as a guy who desperately wants to be a "Seth Rogen type." In 'Take This Waltz,' he takes his sheer likability and strips it the to the bone, creating one of cinema's greatest broken hearts in modern cinema. In '50/50,' the "stoner best buddy" version of Rogen is reinvented as realistically as possible and his riffing with a cancer-stricken Joseph Gordon-Levitt rings absolutely true. Do all of these characters contain his usual Rogen-isms? Sure, but they also represent him taking his persona and coloring it to match eclectic material, effortlessly sliding into projects that would reject an actor with lesser ambition.

And that's why even a dud like 'The Green Hornet' is a valuable example of Rogen's talents. He doesn't play the iconic hero a total goofball, but rather a fairly competent hero. Rogen, a comedian, pays more respect to his classic hero than more serious 'The Lone Ranger' did for its its title character.

Rogen continues to be a generous co-star and an actor willing to take risks, but his ambition continues to impress. His directorial debut (with Goldberg), 'This is the End,' which bears the hallmarks of a post-Apatow comedy (raunchy jokes, tons of improv, plenty of male genitalia, touching bromance) but none of the style. This is a geekier film, a movie that grounds its comedy in the fantastical instead of the realistic. It isn't just a comedy set during the apocalypse, but a genuine, honest-to-goodness apocalypse movie that happens to be stuffed full of dick jokes. Rogen and Goldberg are so busy distracting you with the comedy that they let the actual stakes sneak up on you. Sure, Rogen is playing his slacker-best-friend type, but he's doing it in service of a story filled with monsters and action and characters we actually like getting horribly killed. 'This is the End' showcases a Rogen who could make a genuinely thrilling horror movie if he put his mind to it.

Perhaps that's why he feels like a perfect fit for AMC's adaptation of 'Preacher' adaptation, which combines blasphemous gross-out comedy with a massive scope and characters torn straight out of a Western. Perhaps that's why the news that he's developing a movie based on the war between Nintendo and Sega in the '90s feels like great news. Rogen has yet to rest on his laurels. Just when you think he's done all he can done, he pulls out something new. It's been 15 years since he made his Hollywood debut and he's still learning and experimenting.

And he's acknowledging his age, too. In 'Neighbors,' Rogen tries something new. Instead of playing that stoned slacker, he's playing the responsible father and husband that the stoned slacker grew up into. Rogen may not be done playing man-children, but he's showcasing a willingness to grow up and let the young people (like the shockingly funny Zac Efron) have their turn in that particular spotlight. Too many comics refuse to change. Too many movie stars feel like yesterday's news after a decade in the business. Rogen feels like he's just getting started, like we haven't seen anything yet. How exciting is that?

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