Spoiler 3x21 The Dead Pool

We’re not gonna lie, the title of Castle episode, “The Dead Pool," kinda creeps us out. Or at least it did, until we read this little SpoilerTV article, which teases that the episode is about an up-and-coming swimmer who ends up cadaverous. Oh! Makes much more sense.

OK, so here’s what we know about “The Dead Pool” so far: The main characters are Coach Eric Rome, an NYU swimming coach, and "Rocket" Rob Thompson, a five-time Olympic Gold Medalist. Both know about (and seem extremely distraught by) the news of the death of Zack Jenson, a hot young swimmer about to make it big. We’re just speculating here, but it totally sounds like the “Rocket” is scared the little guy was gonna catch up to him — and sets out to “handle” him? Or maybe that’s exactly what they want us to think. Those Castle guys sure are tricky.

Another factoid about the ep? An ambitious character named Alex Conrad, after having just finished up his first-ever mystery novel, comes to find his idol while hanging out in NYC. Who’s that, you ask? None other than Mr. Richard Castle.

We’re not gonna lie, the title of Castle episode, “The Dead Pool," kinda creeps us out. Or at least it did, until we read this little SpoilerTV article, which teases that the episode is about an up-and-coming swimmer who ends up cadaverous. Oh! Makes much more sense.

OK, so here’s what we know about “The Dead Pool” so far: The main characters are Coach Eric Rome, an NYU swimming coach, and "Rocket" Rob Thompson, a five-time Olympic Gold Medalist. Both know about (and seem extremely distraught by) the news of the death of Zack Jenson, a hot young swimmer about to make it big. We’re just speculating here, but it totally sounds like the “Rocket” is scared the little guy was gonna catch up to him — and sets out to “handle” him? Or maybe that’s exactly what they want us to think. Those Castle guys sure are tricky.

Another factoid about the ep? An ambitious character named Alex Conrad, after having just finished up his first-ever mystery novel, comes to find his idol while hanging out in NYC. Who’s that, you ask? None other than Mr. Richard Castle.

Castle Exclusive: Lie to Me Star Sets His Sights on Beckett
What happens when a mystery writer has his muse stolen by his protégé? If the writer is the title character of ABC's Castle, the answer is simple: It gets combative.

TVGuide.com has learned exclusively that Lie to Me star Brendan Hines has been tapped to play Alex Conrad, a first-time mystery writer who owes some of his debut novel's success to a glowing review written by Castle (Nathan Fillion). When Castle invites Alex down to the precinct to play mentor, however, Alex becomes much more interested in what Beckett (Stana Katic) has to say about being a police detective.

As Castle and Beckett investigate a swimming star's murder, Castle becomes increasingly agitated by how willingly (and privately) Beckett shares information with the newbie author. But don't think the jealous Castle will go down without a fight.

The episode also guest-stars Make It or Break It's Josie Loren and Justin Bruening, the star of NBC's short-lived Knight Rider reboot. Bruening plays the victim's swimming coach, while Loren plays the victim's former girlfriend. Naturally, they both become suspects.

Watch full episodes and clips of Castle in our Online Video Guide

Besides his work as Eli Loker on Fox's Lie to Me, the 34-year-old Hines has also appeared on The Middleman and Terminator: The Sarah Connor Chronicles.

Castle airs Mondays at 10/9c on ABC. Hines' episode, titled "The Dead Pool," is slated to air sometime in April.

I love that Brendan Hines is going to stir up jealousy on Castle. What else can you tell me? — Monica

ADAM: While Castle is plenty peeved by the easy rapport his protégé establishes with Beckett, his remedy is to kill the young pup with kindness. And what better way to do that than to invite him to a mystery writers' poker night? Of course, after the cards are dealt, real-life novelists Michael Connelly and Dennis Lehane make it embarrassingly clear that Hines' character still has plenty to learn before he can truly throw in his chips with the big boys.

Vuelven las partidas de poquer!!!

Thank you for your Nathan Fillion cover! I love Castle and am going to frame it. Now that you’re buttered up, maybe you can give us something on Castle? — Cassandra

Dealing with bloody crime scenes, you’d think Castle (Nathan Fillion) and Beckett (Stana Katic) were used to seeing red, but that’s far from the case when the mystery writer notices his writing mentor catching his partner’s eye in an upcoming episode titled “The Dead Pool.” “Beckett thinks [Castle's friend] is funny, and Castle suffers a bit of muse jealousy,” teases executive producer Laurie Zaks. “[Castle] sets out to set him straight.”

CASTLE – “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, on “Castle,” MONDAY, APRIL 11 (10:01-11:00 p.m. ET) on the ABC Television Network.