Beckett and Castle uncover who's responsible for two deaths in a circle of wealthy prep school students. The character dynamics continue to find their way. This episode, the preppies' partying is juxtaposed with Alexis Castle's personal scruples.
It's nice to see Castle not chase and physically disarm bad guys as he did in the pilot. This fits his observer status, but I wonder if an observer would be allowed to question suspects to the degree he has. I guess the alternative is for Castle to sit or stand by quietly while Beckett does the talking, and we don't want a lead actor to do too much of that. If Avery Brooks had been as calm and quiet as Hawk is in Robert B. Parker's Spenser books, we wouldn't remember his performance twenty years later.
I thought I'd seen the sociopathic punk culprit before, and I had. Nolan Gerard Funk was in the pilot of Lie to Me as Dan, of whom Lightman asks, "Are you going to have sex with my daughter tonight?"
He also played the timid, well-meaning Zach Greenfield, who nonetheless helped train Kryptonite-enhanced dogs in the Smallville episode "Krypto".