Castle (2009): Season 3, Episode 21

3 - 21: The Dead Pool

When a champion swimmer and Olympic hopeful is found dead in a training pool, Castle & Beckett dive in to investigate his murder, and uncover myriad secrets that might have led to his death. Also in the episode, crime fiction authors Michael Connelly and Dennis Lehane guest star, offering Castle their insights into the case over a game of poker.