After a couple of weaker episodes, Castle is back with another gripping episode where an old unfinished plot thread is revisited. This time, however, it has nothing to do with the principal two of Castle and Beckett. In the Season 3 episode “3XK”, we were first introduced to the eponymous serial killer whose real name was Jerry Tyson. Unfortunately, his identity was figured out only at the end and he got away scot-free leaving Castle and Ryan with pangs of guilt that they had to come to terms with. Castle for figuring out the killer’s real identity but being powerless to stop him from escaping. Ryan for not reacting quicker and letting Tyson get the drop on him, not to mention losing his service weapon to the serial killer. In “Kick The Ballistics”, the fourth episode of Season 4, the latter thread is given some much-needed attention.

The episode begins on the usual lighter note with the writers even finding time to squeeze in a Caskett moment as Castle enquires Beckett about her amnesia from “that” day. The victim is revealed to be college student Jane Hertzfeld in what has all the makings of a mob hit. The detectives catch a break with the victim’s ex-boyfriend who happens to have a small record and conveniently enough happens to be involved in the coke-trade. While Ryan and Esposito are interrogating him, however, is when the real bombshell is dropped. The weapon that was used to murder Jane was a Glock-17 and ballistics confirmed that the bullets were a match for Ryan’s stolen service weapon. Welcome back, 3XK!

In the interest of not spoiling for other viewers, I can guarantee that this was a welcome episode after the past two weeks. While the usual Castle wit and charm were lacking for obvious reasons since this was a darker episode, the relationships between the characters got plenty of spotlights. As the trailer suggested, the episode was Ryan-centric as he accompanied Beckett to take runs at suspects, stood in every interrogation and felt personal vendetta to bring the culprits to justice. Seamus Dever proved fully up to the task by anchoring the episode with a solid performance. There were scenes where both his guilt and rage were palpable. Jon Huertas as usual had his moment towards the end where he accompanies his partner as they both disobey orders to crack open the case. The screen time both of them seem to be getting in these early days also bodes well for the series since it is exactly what the fans have been crying out for a long time.

It was not all rosy, however. Victoria Gates continues to be a pain in the ass. I can see why the writers have written her character as an iron-fisted, no-nonsense woman, but that is not what the show needed especially after viewers have gotten used to the tough yet soft Captain Montgomery. I am afraid they may alienate some hardcore viewers if they don’t show some sort of softer side to the new captain; especially if they continue to have her subordinates refer to her as “Sir” which is completely distracting. Another gripe for me personally is the direction Alexis’ character is heading. For a girl who was shown to be so mentally tough, it is really hard to come to grips with all her moaning about missing out on Stanford. I may yet warm up to her once she returns to her old self, but she has proved to be a minor annoyance in these early episodes. Oh well, at least she has stopped whining about Castle’s devotion to Beckett like she did in the first couple of weeks.

The main development to come out of this episode is that the 3XK thread is still fully alive. The writers primarily chose to focus on Ryan’s guilt instead of the triple killer. What this means is that Castle has not yet been absolved of his guilt. I can already see similarities between the 3XK and The Grave Digger from Bones. The latter also had personal history with the primary characters and made appearances in a number of episodes over multiple seasons before being captured. I can envision the writers doing something similar with 3XK as well. Using him to play with the central relationships before closing the plot thread entirely. And given the way this episode ended, that is indeed great news.