In Farmington Hills, MI, Ed Nelson returns home while talking to his friend Lance Jacobsen on his cell phone. Ed reminds Nelson that they both cut corners and that it's just a game. Ed goes to bed but as he sleeps, he's unaware that a tree tattoo has appeared on his arm. He only wakes up when he hears the sound of neighing horses. Invisible ropes suddenly wrap around his wrists and ankles and he screams in agony as the invisible horses at the end of the ropes draw and quarter him.
Dean and Sam are driving and discuss Kevin's translation of the tablets. Realizing that his brother is depressed after losing Amelia, Dean suggests that they take a night off. Sam isn't thrilled with the idea, but they're interrupted when Garth calls. He informs them that he's tracking their GPS signal and directs them to Ed's death in Farmington Hills. Sam figures that they might as well keep hunting while they wait for Kevin to complete the translation.
The brothers go to Ed's apartment and talk to Sheriff Jake Miller, posing as FBI agents. Miller informs them that the apartment was locked from the inside and that Ed collected "toys." Sam notices a suit of chain mail belonging to Ed and spots the tree tattoo on the corpse's arm. Miller tells the Winchesters that a neighbor heard a horse stomping around but they found no hoof prints. He has checked Ed's cell phone and confirmed that he received several bizarre death threat text messages from Lance Jacobsen, and ordered his men to bring Lance in for questioning.
At the police station, Sam and Dean question Lance, who is clearly upset at his friend's death. He explains that he and Ed were players in a local live-action role-playing game, set in the Kingdom of Moondoor. Lance gives them the site's web address and tells them that there are photos posted from the night before confirming he was there. He and Ed were both named to the Queen's Guard but Lance thought Ed broke protocol and challenged him to a duel of sword vs. wand. When Dean wonders if he's talking about real magic wands, a shocked Lance tells him that the wands and swords are fake.
Outside, the brothers figure that Lance probably kill Ed. They check the LARP website and confirm Lance's alibi, and play a promotional video about a battle between the four neighboring kingdoms. The Winchesters are surprised to see Charlie as the Queen of Moondoor.
In the interrogation room, Lance feels an itch on his arm and discovers that a tattoo of a tree has appeared there. He realizes that his eyes and nose are bleeding and looks in the mirror, choking on his own blood.
When the police discover that Lance is dead, they take the body out and check the surveillance footage. The videotape shows that no one touched Lance and Miller figures it's some kind of Ebola virus. Once he leaves, Sam spots the tattoo on Lance's arm but doesn't recognize it. They decide to go to the park that is hosting the LARP and come upon one of the queen's subjects, "Boltar the Furious," locking a shadow orc, Monty, up in the stocks. "Boltar" explains that his real name is Gerry and realizes that the Winchesters' fake FBI badges are fake. He assumes they're doing a cross-genre LARP and refuses to talk to them unless they play the role of medieval knights. The brothers have no choice but to go see Charlie.
Gerry takes the Winchesters to a pitch where Charlie is fighting knights to see if they're worthy of protecting her. She sees the brothers and goes into her tent, and Sam and Dean go after her. She explains that she's assumed a new identity after she helped them fight the Leviathans. Charlie isn't interested in getting involved with homicidal monsters again but the brothers tell her that Ed and Lance are dead. They show her the mark and she recognizes it as a Celtic magic symbol, and admits that a lot of her people have recently had mysterious accidents. She explains that while Ed and Lance didn't have any real-life enemies, their kingdom is at war with the other three kingdoms. Sam figures that someone in another kingdom is using real magic and asks Charlie to stay and help them. Charlie wants to get out and Dean agrees, but Charlie finally admits that it's her people that are dying and that she's tired of running.
Miller calls Sam and tells him that the autopsy report shows that Lance died of belladonna poisoning. However, although he had the symptoms, the coroner found no trace of belladonna in his body. Sam passes the news onto Dean and Charlie and suggests that they canvas the area while he goes to the tech tent and checks on the earlier accidents. Once he leaves, Charlie tells Dean that he'll have to don a costume if he wants to participate.
Sam goes to the tech tent and a young woman, Maria, flirts with him. She's glad to help him with his computer research and brings up an online directory of the injured players.
As he puts on a costume, Dean tells Charlie about how he sent him the fake text message to get him away from Benny. Charlie thinks that it's a dick move but Dean tells her that hunters can't afford attachments. As he broods over it, Charlie wonders if he's thinking of himself but Dean insists that he doesn't have a problem. They go out into the kingdom and Charlie talks about how she got into LARPing because she likes to pretend that she's a hero. Dean points out that she saved their lives and helped defeat the Leviathans and assures Charlie that she is a hero.
Sam uses the directory photos to confirm that all of the injured players had tree tattoos. Maria doesn't recognize the tattoo, and points out that some of the victims were from two of the three rival kingdoms. Only the shadow orcs have avoided taking any injuries, and Sam checks the Internet and learns that the tree tattoo is a mark used to target people with fairy magic.
Dean and Charlie canvas the kingdom's residents and also confirm that the shadow orcs haven't suffered injuries. They go to see Monty, who is still in the stocks, and Dean persuades him to talk. Monty tells them that the tattoo is his liege's family crest and Charlie and Dean head for the shadow kingdom to find the Shadow King.
Once Sam has what he needs, he thanks Maria for her help. She suggests that he come by her tent later but he refuses and leaves.
When Dean and Charlie go into the forest, they find Gerry and Charlie introduces Dean as her new handmaiden. While Dean takes that in, Gerry warns his queen that the forest isn't safe. Dean agrees and gives Charlie his cell phone, and asks her to find Sam and then call him. Once she leaves, Dean has Gerry lead him into the woods.
As Charlie makes her way through the woods, she hears someone following her and circles back. One of the shadow orcs leaps out of the woods, throws a bean bag "spell" at her, and misses. She hits him with a spell of her own and he runs off, defeated. Another figure, robed in black and wearing a stag mask, emerges from the forest and Charlie throws a bean bag at it. It simply stares at her for a moment and then swoops forward.
After failing to find the shadow orcs, Dean and Gerry return to the Moon Kingdom. Gerry suggests that they complete the Queen's orders by exchanging Monty and luring the shadow orcs out. He sends Dean to clean the chamber pots and goes to the stock, while Sam arrives. The brothers compare notes and realizes that Charlie never returned.
Charlie wakes up in a medieval tent with a fireplace, and the stag figure watches her without speaking. She tries to get it to respond and then runs out of the tent entrance... only to come back in through the entrance on the other side. Realizing that she's dealing with real magic, Charlie tries to get a response from her captor but it moves ominously toward her. When Charlie says that she just wants her old life back, the stag figure removes her mask, revealing a beautiful woman underneath. She says that she wants her old life back as well.
As night falls, Sam, Dean, and Gerry go out into the woods to make the exchange. The Shadow King and his men arrive and Dean tries to negotiate, but Gerry insists on handling real-life affairs first. Dean finally fires his gun into the air, breaking the rules, and demands answers. The Shadow King, aka attorney Max Hilby, says that his men didn't capture Charlie and that he got sick after the tattoo appeared on his arm. He used it as his family crest and Dean tells him the King and his men to run away. Monty offers to help, explaining that he has a crush on Charlie. He tells the trio that he saw a strange tent down by the creek and that none of the kingdoms own it.
The woman introduces herself to Charlie as Glinda, a fairy from the Hollow Forest of Arkhmoor. She explains that a man summoned her there with a spell and forces her to hurt people. Glinda doesn't know the man's name and admits that in the last two attacks he forced her to kill. Charlie tries to explain that they're playing a game and someone is taking it too seriously, but Glinda doesn't understand. The fairy tells Charlie that a hero must destroy her master's book of magic to free her, and Charlie promises to rescue the damsel.
Gerry insists on following Dean and Sam despite the danger, and they find the tent. When they go inside, they discover Charlie and Glinda on the bed, kissing. When they realize that they have visitors, Glinda sees Gerry and warns everyone that he's her new master. When Sam and Dean draw their guns, Gerry forces Glinda to turn the weapons into chicken feathers. He insists that he is really Boltar the Furious and that he bought the spell book on eBay and intended to use the fairy to eliminate his competition so Charlie would accept him as her king. He ordered Glinda to murder Ed and Lance because they broke the rules and used real money to bribe their way onto the Queen's Guard. When Charlie tries to tell him it's just a game, Gerry yells that his life sucks and that he LARPs so that he can be a hero.
Sam suggests that Gerry hand over the book and they work everything out. However, the LARPer refuses, figuring he's better off if he wipes Charlie's memories and kills the brothers. He commands Glinda to transform him fake sword into a real one and then animate a suit of armor to attack them. While Sam fends off the armor, Dean manages to punch Gerry, knocking the book away. Charlie grabs it and stabs it with her dagger, destroying it. When Gerry loses his magic, Dean easily knocks him out. Glinda thanks Charlie for saving her and says that must return to the magic forest, taking Gerry with her to stand trial for his sins. Charlie kisses the fairy and she disappears with the LARPer.
The next morning, Charlie thanks the Winchesters for their help and says that she's decide to stay and make a life for herself rather than run from reality. She assures Dean that she's good and that she's there for them if they need help. Once she returns to her kingdom, Dean admits that trying to have fun probably isn't a good idea and that nothing will help him get over what he's lost. Sam thanks his brother for understanding, and then says having fun might help them both get over what they've lost. Soon, Dean is leading the Kingdom of Moondoor in battle with Sam and Charlie at his side.