Before They Were Stars: The Cast of Castle

Nathan Fillion

Nerd overlord and Twitter regular Nathan Fillion started out playing Joey Buchanan on One Life to Live and was quickly snapped up by shows like The Outer Limits, Two Guys, a Girl, and a Pizza Place, Buffy the Vampire Slayer, and the cult hit Firefly. He also starred in Drive and had a recurring role on Desperate Housewives before once again dipping into the Whedon well as Captain Hammer in Dr. Horrible’s Sing-Along Blog in 2008. Check him out getting his ass (and floppy hair) kicked by Brendan Fraser in 1999’s Blast from the Past.

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Nathan Fillion (Richard Castle)

He knows he’s charming. He knows he’s handsome. He knows he’s got the mad writing skills. Yet nothing stops Castle from repeatedly making a complete fool of himself in front of Beckett. Aside from an undercover kiss and some hugging (in a freezer… while dying…), Castle and Beckett (or “Caskett,” as fans call them) didn't approach a relationship until much later. But the two are now headed for marital bliss or are they?

Stana Katic

Like her fellow Canadian Nathan Fillion, Stana got her start north of the border. In Hollywood, Stana’s episode of Alias in 2004 could be considered her big break. After that, she appeared on The Shield, Jag, ER, 24, and CSI: Miami.

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Stana Katic (Detective Kate Beckett)

Beckett started out as a die-hard Castle fan before he even started tagging along with her to crime scenes. Naturally, she never told him that. After spending some time dismantling her crazy, John Nash-esque matrix wall dedicated to solving her mother’s murder, she seemed to have calmed down a bit—just in time to get shot! Now that she’s recovered and back on the beat, time will tell if Beckett will admit to hearing Castle’s shocking admission. It seems like things worked out for them--sort of.

Molly Quinn My one and only movie photo still 2009

Molly C. Quinn

Pre-Castle, Molly played a bobbysoxer teen in the 2009 Renée Zellweger dramedy My One and Only. Too bad she didn’t get to keep those wheels!

Mitch Haddad/ABC

Molly C. Quinn (Alexis Castle)

From playing indoor laser tag with her dad to getting busted with a boy, responsible Alexis has grown up a lot over the past four seasons, much to Castle’s chagrin. She’s goes to Columbia University and ends up going with a boyfriend to Costa Rica which ends up not working out.

Seth Poppel/Yearbook Library

Susan Sullivan

Seen here glamming it up in the 1960 yearbook from Freeport High School in Freeport, New York, Susan Sullivan is an accomplished actress who is probably best known for her work on Falcon Crest and Dharma and Greg.

Seth Poppel/Yearbook Library, Mitch Haddad/ABC

Susan Sullivan (Martha Rodgers —Castle’s Mom)

A former film and theater goddess, Castle’s mom is frequently seen floating around the house in some spectacular number, even if it is her bathrobe. She gives Castle and Alexis guidance, comic relief, and lots of playful chastisement.

Jon Huertas

Before Castle, Huertas did some guest spots on Jag, Moesha, Touched by an Angel, and many others. In 1999, he became a series regular as Brad on everyone’s favorite magical sitcom featuring a talking cat, Sabrina the Teenage Witch. Watch as Sabrina confuses him—twice!

Adam Taylor/ABC

Jon Huertas (Detective Javier Esposito)

“Yo.” Handy with a one-liner, Esposito’s got a casual nature that combines with ferocious loyalty and a somewhat bromance-ish relationship with Ryan. He and Lanie are still going strong, even after trying to conceal their relationship at first. Esposito is almost always right (in his mind) and never fails to put Castle in his place.

Seamus Dever

Before he was Detective Ryan, Seamus Dever had been seen in shows like Crossing Jordan, Without a Trace (pictured), NCIS, and Army Wives, among others.

Jordin Althaus/ABC

Seamus Dever (Detective Kevin Ryan)

You can’t have “Ryan and Esposito” without Ryan. He and Esposito do most of the dirty work, while still fitting in time to tease Beckett and mock Castle. Like all the other main characters except the two leads, Ryan also has a significant other that didn’t take four years to sort out.

Tamala Jones

Before she sliced and diced gruesome bodies on Castle, Jones was seen in Veronica’s Closet, The Wood (pictured), ER, The Tracy Morgan Show, and My Name Is Earl.

Eric Mccandless/ABC

Tamala Jones (Dr. Lanie Parish)

Lanie provides the medical know-how for the precinct and is close friends with Beckett, whom she used to chide regularly about not getting together with Castle. And how can we forget her unexpected sultry singing from the "The Blue Butterfly" episode?

Penny Johnson

Penny Johnson, seen here as regular Beverly Barnes on The Larry Sanders Show, got her start back in the '80s. She’s been on Hill Street Blues, The Jeffersons, Columbo, Star Trek: TNG, and much more. You might also recognize her as Kasidy Yates from Star Trek: Deep Space Nine or Sherry Palmer on 24. The nerd roots run deep on Castle.

Karen Neal/ABC

Penny Johnson (Captain Victoria Gates)

New to the show this season, Capt. Gates picked up where Capt. Montgomery left off, mainly because he was killed after being discovered as both a snitch and a traitor. You have to multitask to get ahead these days, I tell ya. Capt. Gates is no-nonsense, and she’s still not entirely convinced that Castle makes a productive addition to the team.