Castle and Beckett are let in Matthew's apartment by his landlord. Castle discovers that Matthew was drawing a graphic novel. Beckett sees that he went to Barker's school of design. The landlord says Matthew got in a fight with a woman who had long black hair. She says the girlfriend was supposed to be famous. Castle looks in his computer history and finds a website about a woman named Vixen. They find that Vixen runs a coven called Den of Iniquity. Ryan says he had a girlfriend that was into vampire lifestyle, but the deal breaker was when she wanted to have sex in a coffin. They ask Ryan if they can contact her to find out about the next meeting for the vampire club.

Castle and Beckett enter the club and find Vixen drinking blood from a woman's wrist. They ask her if she knows Crow. She says she does and asks if he is in trouble. They inform her they found him with a stake through his heart. She gets upset and wonders who would kill Crow. Vixen admits Crow was one of her lovers. She says she got into a fight with Crow because he was seeing someone named Daemon, but made up with him. He says Daemon fell in love with Matthew and his art. She explains the graphic novels he wrote is based on a man named Morgan Lockerby. She says Morgan really believed he was a vampire and hung out in graveyards at night.

Beckett asks Castle why people are into vampires. Castle explains people are looking for a place to fit in. She says she doesn't get the fascination with the macabre. Castle says something probably happened to them when they were younger. Esposito reports that Matthew's last name is Freeman and has family in Connecticut. She orders them to look for Daemon and Morgan. Before she makes a call to Matt's parents, she tells Castle she hates informing people about lost loved ones.

Later, Beckett meets with Matthew's parents Al and Janice and his sister Rosie. They explain that Matt dropped out of school and changed after he got into vampire culture. Janice says Matthew started to become moody. The last time they spoke to Matt, he sounded upset.

Esposito says that Morgan was committed to a mental hospital by the state, but he escaped. Esposito asks Beckett if she is going to Castle's party and she says she hasn't decided yet. Esposito says if she wants to see his costume, she has to show up. Castle tells Beckett that Matthew's graphic novel isn't that bad. Castle recognizes Morgan's picture as one of Matthew's characters named Morlock. As Beckett gets close, Castle says she smells like cherries. Esposito says there is no trail of Morgan. Castle looks at the graphic novel and sees Morlock on one of the streets of New York. They go to the location and use the comic as a guide. They find a coffin in a room. After Beckett and Castle coordinate to open the coffin at the same time, Castle is frightened even though it is empty. After Esposito makes fun of Castle's reaction, Morlock drops down and attacks Castle. They break a glass window which causes a ray of light to enter the room. Esposito declares that Morlock is really a vampire after he sees the sun burn his skin.