A woman is found dead in a cheap motel's rooftop water tank. But this apparent new tenant street hooker has far more twists and turns than meets the eye, and they involve a dead friend and a big-money law firm. Meanwhile, Beckett is offered a job on the Attorney General's Security Task Force in Washington, DC—a dream job for someone like her—but she can't bring herself to tell anyone else, especially Castle, for fear of what the revelation might mean for her relationships—especially Caskett.
Tropes in use:
- Amoral Attorney: Zigzagged. The second victim helped cover up the misdeed Erika was investigating but was apparently horribly guilt-ridden about it and couldn't function in his career afterwards. Meanwhile, Jessica Banks, the head of the firm, is initially open with the detectives' investigations but shuts them down when they start pointing fingers at a client, with it being unclear whether she knows of his involvement for sure or is just being protective and Properly Paranoid about police questions. The principal of attorney-client privilege requiring the lawyers to defend their clients well and keep their mouths shut under such circumstances also gets referenced.
- Badass Bureaucrat: The man who interviews Becket for her DC job shows shades of this with an air of competence, authority and common sense as he seeks to build the task force.
- Bait-and-Switch: Castle's last line in the episode (See Wham Line below) sounds rather like a prelude to a break up. Before he gets on one knee and produces an engagement ring.
- Cliffhanger: The final scene of the episode (and by extension, the season) ends with Castle proposing to Beckett right after she's decided to take the job in DC.
- Continuity Nod: When the woman who takes the bloody shower wakes up, the Page Brothers hit "Move That Ass" is playing in the background.
- Hero of Another Story: Erika Albrook, the Amateur Sleuth Victim of the Week, was an honors computer science student at Harvard out to expose the cover-up of her friend's death in a drunk driving crash. She had a pretty clever way of staying under the radar by living in a Skid Row apartment to get anonymous access to their wi-fi and playing audiotapes of people having sex to trick everyone into thinking she was just a prostitute. In an episode with a major focus on the Castle and Beckett plotline, her story still manages to be pretty captivating.
- I Just Want to Be Loved: Implied to be the motivation of the perp, with Castle and Beckett speculating he was promised a place at the family table back.
- The Internet Is for Porn: Referenced when Tory talks about how most of the IP dresses in the apartment Erika was staying at were to porn sites.
- "The Reason You Suck" Speech: Beckett gives a pretty good one to a perp who turns out to be the killer.Beckett: Do you have any idea how many people have sat across that table and confessed their sins to me? What makes you think that you're any different, any smarter? You've only been in this room for one hour. But this room...this room has been my life...my home...and I will not let you sit there and lie to me in my own home.
- Ripped from the Headlines: Erika's death was inspired by the real-life death of Elisa Lam
, a visiting Canadian university student who had also checked into a cheap hotel and whose final moments were caught on an elevator surveillance camera shortly before her body was discovered inside said hotel's rooftop water tank. - Wham Line: Castle's final line:Castle: I've been doing a lot of thinking about us, about our relationship, what we have, where we're headed. I've decided I want more. We both deserve more. So whatever happens, whatever you decide... (gets off the swing and gets down on one knee) Katherine Houghton Beckett... (and produces a ring) will you marry me?
