Castle and Beckett investigate the murder of an up-and-coming swimmer. Meanwhile, a younger writer Castle helped get published seems to be interested in Beckett, much to Castle's jealousy.
- Call-Back: At the end of the episode, Ryan is briefly heard saying "they used to do this to me for talking in class", something he quipped to Hal Lockwood when the latter was waterboarding him and Esposito back in "Knockdown".
- Due to the Dead: At the mystery writers' poker game, when someone dies they leave their chair empty and no one sits there for a year.
- Foreshadowing: The team discover steroids in Zack's apartment behind a poster of "Rocket" Rob Tredwyck. Those steroids turn out to be the same kind Rob used to win his first gold medal and Rob killed Zack to keep that from coming out.
- Green-Eyed Monster: Castle loses his shit when Alex connects with Beckett. Alexis talks him out of it... but he takes Alex to his mystery writers' poker game and they tear him apart.
- New Meat: Castle initiates a new mystery writer named Alex Conrad. He's not happy when Alex starts to hit on Beckett. In retaliation, Castle takes him to a poker game with his fellow writers who know what's going on and rip him apart.Michael Connelly: You know what I did after I wrote my first best seller? I shut up and wrote twenty-three more.
- Wrong Genre Savvy: Alex Conrad initially impresses Beckett when he offers his insight on the case, but his inexperience as a mystery writer soon shows:
- When steroids are discovered in Zack's apartment but the tests run on Zack came back negative for steroid use and there were too few vials for him to make any money dealing them, Alex posits that the steroids are a Red Herring. The steroids are in fact why Zack was murdered, just not for the reasons initially thought.
- When Castle invites Alex to a poker night with various other mystery writers where they discuss the case, Alex suggests that Zack was murdered by his ex-girlfriend. The more experienced writers mock him for using the Death by Woman Scorned trope and correctly deduce that whoever killed Zack did so to keep their steroid use from getting out.
