Stana Katic and Jonathan Frakes on the Set of Castle Season 5, Episode 6: "The Final Frontier"
Next week on Castle, Rick and Kate investigate the set of a popular sci-fi TV series called Nebula 9. Check out these behind-the-scenes Twitter pictures of stars Nathan Fillion, Stana Katic, and Seamus Dever geeking out with Star Trek vet and director Jonathan Frakes.
Original Air Date: Castle Season 5, Episode 6: "The Final Frontier" airs on Monday, Nov. 5 at 10 p.m. ET on ABC.