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Season 4, Episode 21
Air date April 16, 2012
Written by Alexi Hawley
Directed by John Terlesky
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Season 3   Season 5

Headhunters is the twenty-first episode of the fourth season of Castle.


With tensions rising between Castle and Beckett, Castle finds himself a new partner — Detective Ethan Slaughter (guest star Adam Baldwin, Firefly), a tough and colorful cop from the city's gang unit. But Castle gets more than he bargained for when Slaughter shows him a grittier side of police work that puts Castle in the line of fire like never before.




Main Cast

Guest Cast


Castle: So… they call you the Widowmaker.
Det. Ethan Slaughter: Hey, not my fault they keep sticking me with idiots. Speaking of partners (refer to Beckett), I’ve seen pictures of yours. She’s smoking hot.
Castle: Besides, guys like Slaughter they just float from precinct to precinct. You know, they’re like nomads wandering the streets of New York City kickin’ ass and takin’ names, which isn’t the most original turn of phrase, but the character is so great. It’s really gonna help me shake up this next Nikki Heat book.
Beckett: Yeah, sure. If you live long enough to actually write about it.
Ryan: I feel like he's cheating on us.
Beckett: He's not cheating on us, Ryan. He's just ... branching out.
Dr. Burke: You're upset.
Beckett: No. Yes, okay? fine, yes, I thought that the two of us were actually getting closer together, and now it seems like he is just pulling away.
Dr. Burke: Have you asked him why?.
Beckett: Yes and he said “Oh everything is fine”
Dr. Burke: What makes you think it isn't?
Beckett: Because he´s acting like a complete jackass. He shows up at the precinct with these bimbos hanging on his arm and now he's just running around with another cop.
Dr Burke: Is this other cop a woman?
Beckett: No. No! Why-why do you even ask that? That's not even the point, the point is I don't understand why he is acting like this. I mean, what did I do?
Castle: Redhead?
Slaughter: Yeah.
Castle: About 5'5", blue eyes, intern?
Slaughter: Yeah, you know her?
Castle: That's my daughter!
Slaughter: Seriously? That girl got an ass... Hey. Relax, Sherlock. I'm just playing.
Castle: Alright. As long as we're clear, my daughter's off-limits.

Featured Music


  • Coffee once again is a weathervane of Castle's relationship with Beckett. Castle offers Beckett coffee, which she eagerly accepts. However, when she realizes that it's just to learn about Slaughter, she puts the coffee down. Castle's gift of coffee has always been a symbol of their partnership; by using it as an obvious bribe, Castle is not just distancing himself from her, he's also casting doubt on what they might ever have had. Much as he believes she already had in "47 Seconds".
  • This is Castle's second encounter with the Westies. In both cases, a Westie was the victim. Finn Rourke, leader of the gang, is mentioned but not seen in this episode.
  • Although Castle gets into several fights in this episode, his "action theme" (as played in Home Is Where the Heart Stops, Last Call, and others) is not used.
    • Castle has gotten into fist fights before, with varying success. He won out against two highly trained assassins, Dick Coonan and Hal Lockwood, beating the latter into unconsciousness with his bare hands. However, he was taken down by a stray punch in Love Me Dead, and usually avoids physical violence. In this episode, his combat skills were minimal again. His performance may be a reflection of psychology and motivation more than physical ability.
  • Ryan suggests that Castle is "cheating" on his friends by shadowing Detective Slaughter. However, he's actually hooking up with an old flame. Actor Nathan Fillion co-starred with Adam Baldwin in the short-lived but beloved series Firefly. Among the many Firefly references in this episode:
    • The episode opens with Castle playing with dolls action figures. This mirrors a similar opening for one of the main cast (Wash) in Firefly, including the fact that one is a dinosaur. The dolls in that episode were intended to foreshadow Adam Baldwin's character betrayal of his crewmates.
    • In an attempt to persuade Slaughter to let him accompany him, Castle gives Slaughter his brown coat. Nathan Fillion's character in Firefly wore a brown coat, and was a former soldier with the "Browncoats"; Firefly fans sometimes refer to themselves as Browncoats as well. Baldwin was actually allowed to keep the coat. He wore the coat to Comic Con 2012, at both the Firefly 10 year reunion panel and the Nerd HQ charity panel which followed (both featuring Nathan Fillion).
    • Fillion's character has a fist fight in a bar while Baldwin's character looks on, eating peanuts, mirroring a similar scene in a Firefly episode, The Train Job.
    • Alexis's contention that "the Universe" might be sending her a sign is a reference to both "A Deadly Affair" (when Castle, also on the outs with the 12th, wins his way back into their good graces), as well as Firefly, where the notion that the Universe sends signs comes up frequently.
    • During an interrogation one of the suspects mentions a theft of medical supplies. Fillon's and Baldwin's characters stole medical supplies from a hospital in the Firefly episode, Ariel, and also from a train in The Train Job.
  • Slaughter tells Castle not to use the word "awesome," explaining: "You're a grown man". In Baldwin's previous TV series, Chuck, one of the main characters was nicknamed Captain Awesome.
  • Castle waits outside as Slaughter questions his "informant". Next to him, a sign reads, "Blood will out."
  • Castle is in the process of writing Frozen Heat, the fourth Nikki Heat novel, and the last one required by his contract.
  • Slaughter's original reaction to the TV camera and Castle's comment to Martha are both almost identical to the set-up of the 1991 film "The Hard Way", in which an actor (played byMichael J. Fox) wants to shadow a cop (James Woods) in a very similar manner.
  • This is the second episode that neither Lanie Parish nor Sidney Perlmutter appears as the medical examiner. The first episode was Nikki Heat.
  • Alexis receives news that she got accepted to Stanford.

Notes and References

External links