How can someone who conveys cool with such ease be such an all-around geek? That’s the question that one is faced with while spending more than a few minutes with Captain Mal Reynolds, Richard Castle, superhero Hal Jordan/Green Lantern, Captain Hammer, and John Nolan in the form of their real-life alter ego, Nathan Fillion.

And there’s nothing put on about said geekiness, having begun with a passion for comic books and unicycles as a kid and continually manifesting itself throughout his life. His connection to geek culture was probably most driven home to him a few years ago when he attended a reunion panel for his sci-fi series Firefly at San Diego Comic-Con. “We had a hall with 7,000 people in it, and I was told they oversold the panel by 20,000,” Nathan says in awe. “I was in my hotel room that morning looking down on this lineup that weaved back and forth under these tents, went down the street, stopped for a crosswalk then started again and went halfway down to the harbor, wound back all the way across the other side of the harbor, and then halfway back again. I thought, ‘What are those people waiting for?’ Because they’d been there all night. It turned out to be Firefly. It was all those years ago and for 14 episodes.” He pauses, a little overwhelmed with emotion, before adding, “I’m glad to know that I’m not alone in my love for the show.”

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(Photo by Frazer Harrison/Getty Images)

He’s not.

Born March 27, 1971, in Edmonton, Alberta, Canada, Fillion had every intention of becoming a teacher, while pursuing his acting “habit” on the side. That habit became a full-blown addiction when he eventually found himself in New York and cast on the ABC soap opera One Life to Live. Three years later he took a chance by moving to Los Angeles to see if he could make it in Hollywood, where he scored a recurring role in the sitcom Two Guys, a Girl and a Pizza Place, a part in Steven Spielberg’s Saving Private Ryan, and the villainous role as Caleb on Joss Whedon’s Buffy the Vampire Slayer. Firefly, the Whedon-produced short-lived series, hit in 2002 and Fillion has been undergoing geek ascendency ever since, providing his voice for such animated efforts as King of the Hill, Justice League Unlimited, and, as Green Lantern, in a couple of DC animated DVD films, as well as the video games Jade Empire and Halo 3.

In between, he starred in Tim Minear’s short-lived Drive, had a recurring role on Desperate Housewives, and was cast in the starring role of mystery writer Richard Castle in ABC’s Castle, which ran for eight seasons. Plus there have been forays to the web in such online productions as Spike’s PG Porn, The Guild, Husbands, Tim Daly’s The Daly Show, and, most notably, Whedon’s Dr. Horrible’s Sing-Along Blog. The two teamed up again for a modern-day adaptation of Shakespeare’s Much Ado About Nothing.

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(ABC/Matt Petit)

Currently, he’s the star of ABC’s The Rookie, about a guy in his forties who decides to change his life by becoming a cop. He says of his character, John Nolan, that this is a guy experiencing the new norm. “If you’re not going through this,” he noted at Paleyfest, “If you’re not in your forties or going through this right now, you know someone who is. Someone changing career or starting a new romance. This is something that’s happening.”

Doing the show, he’s also gotten the sense of the responsibility of being a cop. “It’s scary as hell,” he explained. “I mean, people don’t call you when it’s good news. When you’re a police officer, they call you when everything’s gone terribly, terribly wrong. You have to have the desire to serve and put yourself in a dangerous position to serve the common public. That’s the scariest time,” Nathan said.

Keep reading for more on Nathan and to check out a never-before-posted Q&A interview between Closer Weekly and the actor!

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