For more than two decades, Nathan Fillion has been one of television’s most charismatic and beloved actors. With his signature wit, warmth, and effortless charm, he’s managed to turn nearly every character he plays into an instant fan favorite. From space cowboys to crime-solving writers to heroic cops, Fillion’s career has spanned genres — proving that his appeal isn’t limited to one role or one type of story.
As The Rookie continues to thrive into its eighth season, it’s the perfect time to look back at Nathan Fillion’s 12 best roles, ranked not just for their popularity, but for the mark they’ve left on his fans and on pop culture.
1. John Nolan — The Rookie (2018–Present)
Fillion’s current role as Officer John Nolan is one of his most grounded and relatable. As the oldest rookie in the LAPD, Nolan’s story is a refreshing mix of humor, vulnerability, and perseverance. Fillion perfectly captures the struggles of starting over later in life, making Nolan both inspiring and deeply human. His chemistry with the cast — especially Melissa O’Neil’s Lucy Chen — has become the emotional heart of the series.
2. Richard Castle — Castle (2009–2016)
If The Rookie is Fillion’s mature phase, Castle was his defining era. Playing Richard Castle, a best-selling mystery novelist who shadows NYPD detective Kate Beckett (Stana Katic), Fillion brought his signature charm and quick wit to every episode. The show’s mix of procedural crime and romantic tension made it a massive hit. Castle remains one of the most iconic “will-they-won’t-they” TV characters of the 2010s — and Fillion’s chemistry with Katic remains legendary.
3. Malcolm “Mal” Reynolds — Firefly (2002–2003) / Serenity (2005)
Before he became a household name, Fillion stole sci-fi fans’ hearts as Captain Malcolm Reynolds in Joss Whedon’s Firefly. A war-weary rebel leading a ragtag crew across the galaxy, Mal embodied the antihero archetype — tough, loyal, and quietly wounded. Although the series was short-lived, its cult following only grew with time, culminating in the 2005 film Serenity. To this day, Fillion’s portrayal of Mal remains one of the most beloved roles in science fiction television history.
4. Caleb — Buffy the Vampire Slayer (2003)
Fillion briefly traded heroism for villainy as Caleb, the sinister, misogynistic preacher in Buffy’s final season. His chilling performance proved he could be just as captivating playing the bad guy. Fillion’s Caleb was both charismatic and terrifying — a memorable departure from his typical good-natured roles.
5. Captain Hammer — Dr. Horrible’s Sing-Along Blog (2008)
Only Nathan Fillion could play a superhero who’s both heroic and hilariously vain. In Joss Whedon’s cult web musical, Fillion’s Captain Hammer serves as the cocky foil to Neil Patrick Harris’s awkward villain, Dr. Horrible. Fillion’s comedic timing and deadpan delivery made every line unforgettable — especially in the musical numbers, where his “heroic” arrogance shines.
6. Joey Buchanan — One Life to Live (1994–1997, 2007)
Before his primetime success, Fillion honed his craft on daytime television. His role as Joey Buchanan on the soap opera One Life to Live earned him a Daytime Emmy nomination and helped launch his career. It was clear even then that his charisma and emotional range would eventually take him far beyond the world of soaps.
7. Dogberry — Much Ado About Nothing (2012)
In Joss Whedon’s modern adaptation of Shakespeare’s Much Ado About Nothing, Fillion turned the bumbling constable Dogberry into one of the film’s standout performances. With comedic flair and impeccable delivery, he made Shakespeare feel effortlessly modern — proving once again that his versatility knows no limits.
8. Hermes — Percy Jackson: Sea of Monsters (2013)
As the messenger god Hermes, Fillion brought levity and humor to Percy Jackson’s mythological world. His version of Hermes was witty, charming, and a bit of a rule-breaker — exactly the kind of role Fillion excels at. Even in a supporting part, he managed to steal every scene he was in.
9. Johnny Donnelly — Two Guys, a Girl and a Pizza Place (1998–2001)
Long before Castle and The Rookie, Fillion charmed sitcom audiences as Johnny Donnelly, the lovable boyfriend (and later husband) of Sharon Carter in this late-’90s comedy. His natural comedic instincts and everyman likability helped the show develop a loyal following and hinted at the charisma that would later define his bigger roles.
10. Green Lantern (Voice) — DC Animated Universe
Fillion’s voice acting as Hal Jordan / Green Lantern in various animated DC projects is a fan-favorite among comic book enthusiasts. His confident, witty, and slightly cocky take on the character feels perfectly in tune with his live-action personas. Many fans even argue that Fillion should’ve played Green Lantern in live action — and honestly, they’re not wrong.
11. Reynolds — The Rookie: Feds (Crossover Appearance)
Fans got a treat when Fillion’s John Nolan made a brief crossover appearance in The Rookie: Feds. His easy chemistry with Niecy Nash-Betts’s Simone Clark and his subtle leadership presence showed how seamlessly Fillion’s character fits into the broader Rookie universe. It was also a reminder that Nolan’s story still has plenty of room to grow across multiple shows.
12. Nathan Drake (Fan Film, 2018)
In one of the most talked-about fan projects of the decade, Fillion starred as Nathan Drake in a short Uncharted fan film that quickly went viral. Fans had long dreamed of seeing him play the wisecracking adventurer, and his performance proved he was born for the role. Even though the official Hollywood adaptation went in another direction, Fillion’s version remains definitive to many fans.
Nathan Fillion’s Legacy
Across every role — from the captain’s chair of Firefly’s Serenity to the streets of Los Angeles in The Rookie — Nathan Fillion brings something rare: authentic charm. He can make audiences laugh, cry, and cheer in the span of a single scene. His characters feel human, no matter the genre.
Whether he’s solving crimes, flying through space, or breaking hearts, Fillion’s presence is magnetic. He’s the kind of actor who makes every project feel a little warmer, a little more fun, and a lot more memorable.
As The Rookie continues to build on his legacy, one thing is clear: Nathan Fillion isn’t just a star — he’s a storyteller whose roles have shaped modern television in ways that will last for decades. 🌟
