Happy 42nd birthday today to Nathan Fillion, who has become almost the archetypical geek heartthrob to many of his endearing fans across the country, as his guy-next-door good looks, fun gregarious charm, and keen acting skills in productions like the cult favorite Firefly and his current gig as the titular character on TV’s Castle has solidified him as an A-lister in geek and sci-fi/fantasy circles.

Fillion had been kicking around Hollywood’s door for quite some time before his current success, appearing in film productions like Steven Spielberg’s Oscar-winning WWII salvo Saving Private Ryan; the sleeper comedy/drama Waitress, and lesser quality fare like Blast From the Past and Dracula 2000. He also appeared in television productions like Spin City, Two Guys and a Girl, and the long-running soap opera One Life to Live before landing the role which made him famous and a cult superstar to many, Captain Malcolm Reynolds, on Firefly, which was a creation birthed by sci-fi/fantasy wonderman Joss Whedon. The show, short-lived and which followed the crew members of Serenity (the name of their space craft), has taken on a gargantuan life of its own since its cancellation after only eleven aired episodes, and in the present day is as arguably as revered feverishly and passionately as Star Trek was and is, by rabid fans coast to coast, a success due to the writing and production style of Whedon, grand writing, and a stellar ensemble cast, led by none other than Nathan Fillion.

No one was more surprised by Firefly‘s steady and overwhelming success post-cancellation than the cast members themselves, including Fillion, who spoke about that and more during the Firefly 10th Anniversary Panel at last year’s New York City Comic-Con, in which Fillion made a surprise appearance to the sheer frenzied delight of the crowd. Due to the home video and internet streaming mediums, Firefly has grown in popularity, and continues to reach new fans as the years go on, introducing and reintroducing Fillion and his cast mates to scores upon scores of fans. The success of this spawned a film in 2005, a one-shot spin off, called Serenity.

The post-Firefly career of Fillion has been more than steady, as he’s been seen cropping up via guest appearances on programs like Lost and Desperate Housewives. His work as a voice actor has been utilized on various programs like American Dad, Robot Chicken, King of the Hill, Justice League Limited, and he’s also been heard on a few videogames as well, like Halo 3, which he was reunited with fellow Firefly cast members Alan Tudyk and Adam Baldwin. And then of course, there’s his current job on Castle, which recently netted him a People’s Choice Award. Fillion’s willingness to stretch himself in the industry with a kind of a fun, roll your sleeves up and have a good time attitude and demeanor adds multitudes to the man and is another part of his charisma among his loyal fans.

So let’s celebrate the birthday of Nathan Fillion today, and there’s plenty of fans that will do so, especially his female ones. Judging by the many memes and jpegs all over the cyber universe and on social media outlets, in which many proclaim that “they love their Captain,” it seems like the loyalty and the passion for Nathan Fillion will ensure that love till the end of time.