Castle and Beckett land a murder case at Supernova Con where Castle is signing his Derek Storm graphic novel. Castle is like a kid in a candy store at the con and it is soon revealed that Beckett was a huge fan of Nebula 9, to which the murder victim is linked.

One of the funniest moments of the show is when Beckett is recognized by a college friend who refers to her as “K Becks.” The glee on Castle’s face when he hears that Beckett used to cosplay and be a huge fan of Nebula 9 is priceless.

Back at the morgue, Castle and Beckett learn that the victim was killed with a laser gun.  Esposito and Ryan head back to the convention to question attendees in interesting costumes, speaking even more interesting languages. Castle stumbles upon the murder weapon when he shoots a laser gun only to find out it actually works. This takes Beckett and Castle to the laser maker who insists he only made two functioning lasers and sold one to a guy in a “griever” costume.

In the end Beckett and Castle bring the group of suspects together on the Nebula 9 experience in order to reveal the murderer. All they need to do is check the suspect’s hands for burns from the laser gun.

After the murder is solved Castle and Beckett negotiate a little roleplaying time. Castle is dying to see Beckett in her Lt. Chloe costume but what he gets in the end is not what he expected.

This episode was loaded with great sci-fi references including several nods to Fillion’s role on Joss Whedon’s Firefly and Battlestar Galactica.

What were some of your favorite sci-fi references?

Next week’s promo for “Swan Song” shows Castle and Beckett pulled into a documentary about rock-and-roll. Check out the promo below and tell us what you think! Will Caskett be caught on tape?