Castle: Witness for the Prosecution is one of two back-to-back episodes of the series, amazingly this is not a two-night two-parter. This episode deals with a crime that Rick sees five months previously and as the eye witness, he is due to testify against the alleged murderer Nina O’Keefe (Clare Grant).
At a charity auction book reading for the Masters family, news correspondent Sadie Beakman appears to be stabbed to death by Nina, “caught in the act” by Rick and now he is a witness for the prosecution in O’Keefe’s murder trial. The case appears to be open and shut until the new public defender Caleb Brown (Kristopher Polaha) “nukes” Castle’s testimony setting up justifiable doubt in the jury’s minds.
Rather interestingly, Brown is a “loksat” baddy, as in he has a direct connection to the “big bad” of the season. Vikram Singh (Sunkrish Bala) Kate’s partner in her secondary storyline of hunting down loksat, aka the reason that she and Castle are separated, is looking at Brown as the episode begins.
Later, the public defender shows up as Nina’s attorney and Beckett is surprised. Brown questions Rick on the witness stand and rips his testimony to shreds. This sets up doubt in Castle’s mind as to what he really saw and he, along with the 12th precinct ‘A’ team re-investigate the murder.
While Rick sets out to initially prove that he was right about Nina murdering Beakman, he ends up believing in her innocence. By the end of the episode, Beckett, Rick, Javi and Ryan all go that extra mile to prove O’Keefe’s innocence. Kate also has ends up with a grudging respect for Caleb, who initially appeared in the episode Mr. and Mrs. Castle.
Brown is obviously going to be the joker in this season’s storyline. As Kate tells Vikram, the public defender is a monster, but one with what could be seen as a fatal weakness; he craves justice for his clients.
Overall, Witness for the Prosecution feels a little like Perry Mason, sans a charismatic lawyer who rules the courtroom and stops proceedings with last minute information. In this episode it is Castle and Kate who interrupt the trial to present information that will, ultimately, prove Nina’s innocence.

Despite the fact that Brown’s character is clearly a new recurring one, not a lot of time is spent on the man’s attachment to loksat. Instead the episode allows Richard to set up another of his cockeyed plans, which ultimately always work out, where he gets the judge to jail him for contempt giving him access to Nina.
This storyline has Nina as the lesbian lover of the news correspondent and the dead woman’s cameraman as kidnapper. Included in this mystery is a duffel bag with $5 million that was stolen by the deceased and then split with her “loyal” cameraman.
At the end of the episode, the woman’s killer turns out to be her husband, who Castle also saw the night of the murder. Keeping with its Perry Mason overtones, Beakman not only confesses to killing his wife at the trial, but Kate arrests him there as well. Richard solves the crime during the dramatic moment where he and Beckett interrupt the trial.
Comically, Nathan Fillion manages to raise a few chuckles, although the Svetlana outrage from last week were Javi and Ryan are furious with Rick was dropped this week. The three worked very well as a trio of interrogators when they questioned Mr. Masters, the first suspect aside from Nina.
While it is annoying that in terms of character arc, Rick Castle seems to have taken a giant step backward, there is a hint in the episode that Kate is tiring of the charade that she and Richard are separated. She tells Vikram, in an amusing scene where she learns the IT expert has named his computer “Cee Cee,” that she is ready to get her life back.
It is still interesting to see that new cast member Toks Olagundoye as Hayley Vargas is still missing from the show. In terms of “new characters” this episode does more properly get into introducing Caleb Brown as a bit more than shadowy loksat villain.
Witness for the Prosecution was amusing enough, even going so far as one character getting an offer to be in Castle’s next book if she forced her husband into giving up evidence without a search warrant. The next episode, airing February 15, the day after “Witness” is Dead Red in this back-to-back double-header that seemingly has no connection.
Castle normally airs Mondays on ABC.