The episode begins with a Nebula 9 experience and we see that a woman is just lying around. She appears to be a part of the show but later we see that she is actually dead. Richard is signing his copies of the Storm Season. Kate arrives declaring that there is a murder that took place in the Supernova Convention. Shiny! He tells her that he used to attend this convention every year with Alexis and he feels that it is a genius idea to commit a murder here. Alexis used to dress up like Princes Leah and he was Dart Vader. Castle doesn’t seem to be a fan of Nebula 9; but he seems to like the ship despite the show being lame. The victim is Annabelle Collins.
She is the one who put together the Nebula 9 fan experience. Looks like she was killed and then stashed into the pod! Gabriel Winters arrives. He is the Captain of the ship. Ryan says that he hasn’t spoken anything yet. Kate is awed when she sees him but she quickly masks it and walks up to Gabriel to ask him about Annabelle’s death. But he doesn’t seem to know much. He says that he saw Anna at nine last night. He doesn’t know about her family but he says that her friends Audrey and Davis run the booth downstairs. Audrey tells them that last morning Anna was upset as someone she trusted had betrayed her. But she doesn’t know anything else. Davis tells them that Anna received some threat mails when she started the fan club. Kate wants to know why Castle hates Nebula 9 and he tells her that it is cheesy and defies laws of Physics.
Just then Henry, an old friend calls out to Kate and hugs her. Henry reveals that Kate is a Nebula 9 fan and she even used to wear the Nebula 9 outfit. Henry then shows Castle an old photo where Kate is dressed as Chloe. She takes the photo from him. Castle tells her that he will pardon her terrible taste if she wears the costume for him. They then go to the morgue and the coroner tells them that Anna was killed by a high intensity laser beam. A real sci-fi murder at a real sci-fi convention!!This keeps getting better. Castle says that it could be the work of some crazed fans; but Kate says that all of them have alibis. He thinks that someone fashioned the laser beam to kill Anna with the exact Nebula 9 weapon. Ryan and Esposito talk to some people from the convention.
One girl tells Ryan that she saw Anna with Stephanie Fry; the woman who played original Chloe. Stephanie is a big movie star now and she isn’t even involved with Nebula 9 anymore. Kate goes to talk to Stephanie. She says that it was a quick talk and Anna asked her if she could be a part of this week’s Nebula 9 experience. She says that Anna was desperate as she didn’t have a proper cast member. Stephanie says that Anna was having problems with Gabriel, Capt. Max. Ryan tells them that Gabriel was showing up late to the fan experience drunk. In fact he was a no show for one of the experience and Anna had to pull him out of his hotel where he was with two naked women. Esposito tells her that Gabriel was a washed up actor and Anna wanted to remove him. He might have motive.
Castle sees Alexis walking around the convention and she is scantily dressed. Kate takes him away as Castle was overreacting. Kate and Castle then walk into the ship and Gabriel says he has nothing to do with the murder. Castle checks his laser blaster and they see that it works just like a real weapon. This could be their murder weapon. Esposito confirms that the blaster is definitely their murder weapon. Gabriel says that the blaster did not belong to him as he grabbed it from the prop table as he normally does when he suits up. He says that they did have clashes but they also had an understanding. He then mentions her boyfriend but Kate says that there is no evidence that she had one.
He says that last night he was attending to a personal issue. On being pressed, he says that thanks to his ‘romances” he was left with a burning desire to consult his doctor. Ouch, it just got worse! The alibi checks out as the doctor confirms that he was dosing Gabriel with antibiotics at the time of the murder. Ryan thinks Anna had a secret boyfriend. Esposito traces the laser blaster. Ryan and Esposito go to the convention, hoping to id the guy Anna was with. The bartender says that she was with a date but later she was at the bar crying. He says that the guy was also wearing the exclusive VIP badge. Next, Kate and Castle arrive at the store and they enter it, ignoring the warning sign.
They get locked inside and then they are targeted with laser beams. Kate announces herself and the laser beams are lowered and an old man steps out. He is Benjamin Donnelley and he prepares sci-fi equipment for enthusiasts. Kate tells him that they are looking for a Thorian blaster. He says that his blaster is not designed to kill; it is only for entertainment purposes. He says he sold one to a collector on Wednesday night. He doesn’t remember his name but he was wearing a creaver’s costume and drove away in a white SUV. He says the plates were from North Carolina. Kate knows that the creavers are sworn enemies of the Nebula 9 crew.
The next day, Esposito tells Kate that they managed to track down the guy with the VIP pass and only one person had an SUV with NC plates; Simon Westport. They also found the creaver outfit in his truck. They bring in Simon. Simon says that he bought the gun as a gift for Anna. He did know about her death until the police told him. He says that he did have an affair with her but that night at the party when he went out to take a call and came back, he saw a guy hassling her. He tried to kiss her and she slapped him and she was upset. Simon identifies the guy as Davis. Kate questions Davis.
Davis tells her that he always liked Anna despite being with Audrey and that night when he saw her with her boyfriend, he went crazy and wanted to tell her how he really felt about her. She freaked out and said that she will have to tell Audrey. But he says that he did not kill Anna as he way half way across the building when the murder took place. Davis says that Anna was so upset with this that she was going to end the fan experience and move on. She was going to sell the rights. And in case of Anna’s death, the rights would go to Audrey. Esposito tells Kate that Audrey signed a deal for 2.5 million and sold the rights. They confront Audrey but she says nothing.
Next, Kate and Castle are on the ship and Kate tells her how she identified with the show and asks Castle to stop making fun of her. Castle touches on of the equipments and he sees strange marks on his hand that is visible only under the UV light. Guess they just solved the murder. They then call all the people who had some relation with Anna and they examine their hands under the UV lights. They explain that the laser blaster leaves a burn mark on the hand and it is visible only under the UV light. Castle had tried firing it earlier and so he had those marks on his hand. They then see that Gabriel has those marks but he says that he bought the laser blaster and the marks are from this morning when he tried using it on the hotel walls. Stephanie tries to escape and Kate sees that she has the burn marks.
Stephanie grabs the blaster from Gabriel and points it on his head. She says that she tried very hard to get away from this crappy show and now with Anna selling the rights; it was going to start all over again. But now she says that she will blow Gabriel’s head and put an end to it. Gabriel tackles her and grabs the blaster from her. Stephanie is under arrest. Next, Castle wants to see Kate in her old costume. She agrees. She wears the costume and we see that the bottom is sexy but she is wearing a scary mask. Castle runs out of the room. The episode ends.