Nathan Fillion is sound asleep. After working all weekend, he is catching some much-needed Monday z's in his modest and cozy trailer on the set of the hit ABC crime dramedy Castle. But because Fillion is a man of the people, he rouses himself from his slumber to welcome a visiting reporter. He even offers treats. ''Girl Scout cookies?'' says the actor, sporting dark slacks and a white T-shirt but not looking the least bit rumpled from his power nap. ''I have Samoas, but no Thin Mints. I'm not a Thin Mint kind of guy.'' After clearing a spot to sit and switching off the TV (he was watching Avatar; he says having some background noise helps him rest), Fillion reflects on the topsy-turvy ride that has seen him go from being a daytime soap star to a cult action hero to one of network television's most popular leading men. ''I have been very fortunate in my career to have a long streak of projects where I'm thrilled to be part of them,'' he says. ''I don't think I've ever done a job where I said, 'Well, I really need the money.' Everything I've done I've done with an excitement of 'I can't wait to do this!'''
Afterward, Fillion walks over to the set, where he runs into one of the episode's guest stars, Peter Parros. ''Talk about coming full circle Peter and I shared a dressing room on One Life to Live,'' says Fillion with the genuine enthusiasm of reuniting with an old friend. Then he takes his arm. ''Shall we go to work, brother?'' And with that, they march off together in unison.
If Fillion is more polite than most with fans, costars, journalists perhaps it's because he occupies a special place in Hollywood. It started back in 2002, when, thanks to a few key roles from the mind of Joss Whedon Capt. Mal Reynolds in Firefly and its big-screen adaptation, Serenity; an evil preacher in Buffy the Vampire Slayer; and a vain superhero in Dr. Horrible's Sing-Along Blog Fillion began receiving A-list treatment from sci-fi fans, even if he wasn't quite an A-lister himself. And he was more than happy to play to that audience. ''I think of Galaxy Quest and the plight of those pigeonholed actors who don't do anything except for conventions,'' he says. ''To be pigeonholed as a Malcolm Reynolds? Uh, dream. Winning.''