|Kick the Ballistics|
|Season 4, Episode 4|
|Air date||October 10, 2011|
|Written by||Moira Kirland|
|Directed by||Rob Bowman|
While investigating the mysterious shooting death of a young woman, Castle and Beckett face a cop’s worst nightmare when they discover that the gun used in the killing is Det. Ryan’s old service weapon – the one that was stolen by the serial killer, 3XK. Now with the clock ticking, the team must work to solve the murder, track down 3XK and retrieve Ryan’s gun before the killer strikes again.
- Nathan Fillion as Richard Castle
- Stana Katic as Detective Kate Beckett
- Jon Huertas as Detective Javier Esposito
- Seamus Dever as Detective Kevin Ryan
- Tamala Jones as Dr. Lanie Parish
- Penny Johnson Jerald as Captain Victoria Gates
- Molly Quinn as Alexis Castle
- Susan Sullivan as Martha Rodgers
- Ross McCall as Seth Carver
- Tim Jo as Ben Lee
- Billy Lush as Finn McQueen
- Francois Chau as Clifford Lee
- Lanny Joon as Philip Lee
- Mercedes Colon as Philip Lee's Attorney
- Nadine Crocker as Charlotte Rosenberg
- Stephanie Nash as Mrs. Herzfeld
- Joe Martin Thomas as Bodyguard
- Sam Ayers as Bartender
- Michael Yavnieli as Marshall Drooen
- Jessie Graff as Jane Herzfeld (uncredited)
- Castle: Grande skim latte, two pumps sugar free vanilla.
- Beckett: Castle, I think you’ve read my mind.
- Castle: So, how’s Ryan holding up?
- Esposito: Three days after my last tour in Iraq, I’m at a diner with friends. A car backfires. My friends look around, I’m under the table. Ryan’s just waiting for the next hit.
- Beckett: You guys took a helluva chance.
- Ryan: Beckett, you’re starting to sound like our boss.
- Castle: You know, Ryan, none of this is your fault. The fact that he used your gun...
- Ryan: That weapon was issued to me by the City of New York. I let it out of my hand, and now a woman is dead. So please do not tell me that it's not my fault.
- Castle: Execution-style murder, cement trucks? Can anyone else say mob hit? I'm looking at "concrete" evidence right here.
- "Taking Down Lee" - Robert Duncan
- Ryan mentions to Detective Seth Carver that he began as a rookie in Narcotics.
- Esposito has done at least one tour of duty in Iraq, which he mentions to Castle when the writer asks him how Ryan is holding up.
- Ryan announces that Ben is going to LA in witness protection. One, he should not be told this information, Two, he should definitely not be announcing this information.
- Actress and stunt woman Jessie Graff appeared as the murder victim Jane Herzfeld, but also was a stunt player in this episode.
- This episode is featuring an altered title sequence with different music and the title being shown without the pen animation, like in "Countdown" and "Always".
- WATCH OUT: Beckett lies again to Castle regarding her memory on the day she was shot! When Beckett experiences discomfort of the scars Castle asks her if she still has memory post the shot was fired.
- Credited at the end of episode as Marshall Drooen, but was referred to Marshall Mike Drooen by Kevin Ryan