There's a lot to love about Nathan Fillion: his love for all things nerdy, his willingness to embrace flannel and his ability to rock the hell out of a blazer are just a few of the Canadian's qualities.

The "Castle" star turns 43-years-old on March 27 (happy birthday, you old bugger!) and to celebrate, we thought we'd choose our 40 favourite photos of the Edmonton-native, because why not?

To be honest, it was tough narrowing it down to only 40 pics. The former "Firefly" actor has had so many hilarious and hot moments over the years that we could have easily picked out hundreds, but, in the name of time and sanity, we finally chose pics we think represent the funny guy at his best.

Enjoy.

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    LOS ANGELES, CA - NOVEMBER 24: Actors Nathan Fillion and Alicia Silverstone speak onstage during the 2013 American Music Awards at Nokia Theatre L.A. Live on November 24, 2013 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

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    From left, Zachary Levi, Nathan Fillion and Tom Hiddleston arrive at the U.S. premiere of "Thor: The Dark World" at the El Capitan Theatre on Monday, Nov. 4, 2013, in Los Angeles. (Photo by Jordan Strauss/Invision/AP)

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    Nathan Fillion performs with dancers on stage at the 65th Primetime Emmy Awards at Nokia Theatre on Sunday Sept. 22, 2013, in Los Angeles. (Photo by Chris Pizzello/Invision/AP)

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    Nathan Fillion, from left, Neil Patrick Harris, and Sarah Silverman perform on stage at the 65th Primetime Emmy Awards at Nokia Theatre on Sunday Sept. 22, 2013, in Los Angeles. (Photo by Chris Pizzello/Invision/AP)

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    LOS ANGELES, CA - SEPTEMBER 22: Actor Nathan Fillion (L) and actress Mikaela Hoover attend HBO's Annual Primetime Emmy Awards Post Award Reception at The Plaza at the Pacific Design Center on September 22, 2013 in Los Angeles, California. (Photo by Michael Buckner/Getty Images)

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    SAN DIEGO, CA - JULY 19: Actor Nathan Fillion (2nd from R) attends 'The Walking Dead' 10th Anniversary Celebration Event during Comic-Con 2013 on July 19, 2013 in San Diego, California. (Photo by Jason Kempin/Getty Images)

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    HOLLYWOOD, CA - JUNE 05: Actor Nathan Fillion, James Carpinello and actress Amy Acker attend the screening of Lionsgate and Roadside Attractions' 'Much Ado About Nothing' on June 5, 2013 in Hollywood, California. (Photo by Jason Kempin/Getty Images)

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    LOS ANGELES, CA - FEBRUARY 17: Host Nathan Fillion speaks onstage at the 2013 WGAw Writers Guild Awards at JW Marriott Los Angeles at L.A. LIVE on February 17, 2013 in Los Angeles, California. (Photo by Maury Phillips/Getty Images for WGAw)

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    LOS ANGELES, CA - JANUARY 26: Actors Nathan Fillion and Tamala Jones attend the Entertainment Weekly Pre-SAG Party hosted by Essie and Audi held at Chateau Marmont on January 26, 2013 in Los Angeles, California. (Photo by Alexandra Wyman/Getty Images for Entertainment Weekly)

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    BEVERLY HILLS, CA - JANUARY 13: Actors Lea Michele (L) and Nathan Fillion pose in the press room during the 70th Annual Golden Globe Awards held at The Beverly Hilton Hotel on January 13, 2013 in Beverly Hills, California. (Photo by Kevin Winter/Getty Images)

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    LOS ANGELES, CA - JANUARY 09: Actor Nathan Fillion backstage at the 39th Annual People's Choice Awards at Nokia Theatre L.A. Live on January 9, 2013 in Los Angeles, California. (Photo by Jason Kempin/Getty Images for PCA)

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    LOS ANGELES, CA - JANUARY 09: Actor Nathan Fillion poses for a portrait during the 39th Annual People's Choice Awards at Nokia Theatre L.A. Live on January 9, 2013 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for PCA)

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    TORONTO, ON - SEPTEMBER 08: Actors Sean Maher (L) and Nathan Fillion attends the 'Much Ado About Nothing' premiere during the 2012 Toronto International Film Festival at The Elgin Theatre on September 8, 2012 in Toro (Photo by Sarjoun Faour Photography/Getty Images)

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    SAN DIEGO, CA - JULY 14: Actors Nathan Fillion and Zachary Levi attend the Playboy and True Blood 2012 Event on July 14, 2012 in San Diego, California. (Photo by Frazer Harrison/Getty Images For Playboy)

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    SAN DIEGO, CA - JULY 13: Joss Whedon and Nathan Fillion speak onstage at the 'Firefly' 10 Year Anniversary Reunion Press Conference during Comic-Con International 2012 held at the Hilton San Diego Bayfront Hotel on July 13, 2012 in San Diego, California. (Photo by Frazer Harrison/Getty Images)

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    SAN DIEGO, CA - JULY 13: Nathan Fillion speaks onstage at the 'Firefly' 10 Year Anniversary Reunion Press Conference during Comic-Con International 2012 held at the Hilton San Diego Bayfront Hotel on July 13, 2012 in San Diego, California. (Photo by Frazer Harrison/Getty Images)

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    BEVERLY HILLS, CA - MARCH 09: Actors Nathan Fillion and Susan Sullivan arrive to The Paley Center for Media's PaleyFest 2012 honoring 'Castle' at Saban Theatre on March 9, 2012 in Beverly Hills, California. (Photo by Alberto E. Rodriguez/Getty Images)

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    SAN DIEGO, CA - JULY 23: Actors Joss Whedon and Nathan Fillion attend Entertainment Weekly's 5th Annual Comic-Con Celebration sponsored by Batman: Arkham City held at Float, Hard Rock Hotel San Diego on July 23, 2011 in San Diego, California. (Photo by John Shearer/Getty Images For Entertainment Weekly)

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    HOLLYWOOD, CA - MARCH 21: (L-R) Actress Ellen Page, James Gunn, and actor Nathan Fillion arrive at the premiere of IFC Midnight's 'Super' at the Egyptian Theatre on March 21, 2011 in Hollywood, California. (Photo by Kevin Winter/Getty Images)

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    LOS ANGELES, CA - MARCH 19: Actors Nathan Fillion and Rainn Wilson arrive at the premiere of IFC Midnight's 'Super' at the Egyptian Theatre on March 21, 2011 in Hollywood, California. (Photo by Jason Merritt/Getty Images)

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    SAN DIEGO - JULY 23: Actors Nathan Fillion and Rainn Wilson fight onstage at the 'Super' panel discussion during Comic-Con 2010 at San Diego Convention Center on July 23, 2010 in San Diego, California. (Photo by Kevin Winter/Getty Images)

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    LOS ANGELES, CA - SEPTEMBER 22: (L-R) Actors Adam Baldwin and Nathan Fillion pose at the Universal Pictures' premiere of 'Serenity' after party held at Universal Studios on September 22, 2005 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

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    LOS ANGELES, CA - SEPTEMBER 22: (L-R) Actors Amy Acker, Neil Patrick Harris and Nathan Fillion pose at the Universal Pictures' premiere of 'Serenity' after party held at Universal Studios on September 22, 2005 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

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    HOLLYWOOD, CA - DECEMBER 6: Actor Nathan Fillion and guest attend the World Premiere of the movie 'In Good Company' on December 6, 2004 at the Grauman's Chinese Theater, in Hollywood, California. (Photo by Doug Benc/Getty Images)

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    LOS ANGELES - MARCH 9: Actors Nathan Fillion (L) and Elizabeth Banks arrive at the premiere of Universal Picture's 'Slither' at the Vista Theater on March 9, 2006 in Los Angeles, California. (Photo by Kevin Winter/Getty Images)

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    LOS ANGELES, CA - JANUARY 16: Actor Nathan Fillion of the television show 'Castle' attends the Disney/ABC Television Group portion of the 2009 Winter Television Critics Association Press Tour at the Universal Hilton Hotel on January 16, 2009 in Los Angeles, California. (Photo by Frederick M. Brown/Getty Images)

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    NEW YORK - MARCH 01: Actor Nathan Fillion attends Cosmopolitan Magazine's Fun Fearless Males of 2010 at The Mandarin Oriental Hotel on March 1, 2010 in New York City. (Photo by Larry Busacca/Getty Images)

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    LOS ANGELES, CA - AUGUST 29: Actor Nathan Fillion (L) and guest arrive at the 62nd Annual Primetime Emmy Awards held at the Nokia Theatre L.A. Live on August 29, 2010 in Los Angeles, California. (Photo by Frazer Harrison/Getty Images)

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    HOLLYWOOD, CA - MARCH 21: Actors Ellen Page (L) and Nathan Fillion arrive at the premiere of IFC Midnight's 'Super' at the Egyptian Theatre on March 21, 2011 in Hollywood, California. (Photo by Kevin Winter/Getty Images)

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    SAN DIEGO, CA - JULY 14: Actors Molly Quinn, Nathan Fillion and Zachary Levi attend the Playboy and True Blood 2012 Event on July 14, 2012 in San Diego, California. (Photo by Alexandra Wyman/Getty Images For Playboy)

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    SAN DIEGO, CA - JULY 14: Actors Nathan Fillion and Liam McIntyre are seen during Comic-Con International 2012 at the San Diego Convention Center on July 14, 2012 in San Diego, California. (Photo by Frazer Harrison/Getty Images)

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    SAN DIEGO, CA - JULY 14: Actors Nathan Fillion and Zachary Levi attend the Playboy and True Blood 2012 Event on July 14, 2012 in San Diego, California. (Photo by Frazer Harrison/Getty Images For Playboy)

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    LOS ANGELES, CA - JANUARY 09: Actor Nathan Fillion poses for a portrait during the 39th Annual People's Choice Awards at Nokia Theatre L.A. Live on January 9, 2013 in Los Angeles, California. (Photo by Christopher Polk/Getty Images for PCA)

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