A man, Stan Hinkle, is watching baseball and his wife Fran calls to him to take out the garbage. Stan says that the game is in overtime, and an irritated Fran takes the garbage out... unaware that a giant rabbit is watching her from the kitchen window. Fran goes to the dumpster and tosses the garbage in. Inside, Stan calls for another beer. He looks up and sees the rabbit there, holding his beer. It hits Stan with the beer and then stabs him to death with a knife. Fran comes in and stares in horror at the rabbit, screaming.
At the bunker, Sam is in his room praying for an explanation for the visions. Dean comes by and hears him, and asks what he's doing. Sam insists that God is sending him visions about the Darkness, and goes to the main room. Dean figures that they should count on each other, not God, as am looks at all of the pre-Biblical lore that Castiel dug up at Gaza. Dean gets a call from Donna about a "killer bunny."
The Winchesters drive to the sheriff's station at Cottage Grove, Minnesota. Donna greets them and she explains that she got a call about a killer Easter bunny. It took a whole team to get the rabbit into custody, and the head won't come off, and Donna refuses to take any chances. Dean isn't sure it's their kind of case, just as Officer Doug Stover comes over. Doug assures them that they're lucky to have Donna, and smiles at her. He goes back to work and Dean figures that Doug has a crush on Donna. Donna isn't interested in dating cops
Donna takes the brothers to the rabbit's cell. It just sits and stares, and Donna explains that after killing Stan, the rabbit just walked out the door. He has human hands and Donna admits that the fingerprints didn't turn up a prior record. Doug comes in and tells Donna that an officer is reporting an emergency. Once she leaves, Dean advises the rabbit to talk to them. It sits and stares, and then leaps up and grabs Dean by the jacket. Sam sprinkles holy water on it and nothing happens, and he finally pries Dean loose. They realize that it's wearing a Minnesota Tech t-shirt, and has a "Kylie Forever" tattoo on his wrist.
The Winchesters check all of the Kylies in town. The last one is Kylie Jennings, and she recognizes a photo of the map. Kylie explains that it's her 19-year-old boyfriend, Mike. They explain that Mike stabbed Stan, and Kylie says that Mike was acting weird the day before. He went to a thrift shop and they bought costumes for an off-campus party. Mike found a creepy bunny mask and he started acting weird after he put it on. He walked out without paying and left his cell at the register. Kyle insists that Mike is sweet, but he became a different person when he put on the mask.
Donna and Doug take a tranquilized Mike out to the car to transfer him to the hospital. Doug tries to help lift him and Donna takes offense. She struggles to pick Mike up on her own, and asks Doug for some help. Dean calls and Mike gets up and knocks Donna to the ground. When Doug tries to get his nightclub, Mike grabs it and prepares to beat Donna. Doug shoots him and they discover that the rabbit mask has finally fallen off.
That night, Sam, Dean, and Donna take the mask out into the woods. Donna is upset that Mike was innocent, and figures that the mask was controlling him. Sam offers her a box of matches, and Donna burns the mask.
At a high school, Coach Phil Evans is spotting one of his football players. Brock Bruckner. Evans assures Brock that his weight-lifting will pay off and goes to his office. Brock puts in his earphones, lifts some dumbbells, and the air turns cold. Someone dressed as the school's mascot--a harlequin-- comes in, picks up a weight, and goes into Evans office. The coach stares at the figure in surprise, and the harlequin starts beating him. Brock notices and runs in, tackling the figure.
The next day, Donna, Doug, and the Winchesters arrive at the crime scene. Evans is still alive but in a coma, and Donna suggests to Doug that it was a copycat killer. The brothers talk to Brock, who explains what happened. He has no idea who was wearing the costume, and says that it wouldn’t come off. Brock says that the attacker was as strong as he was. Sam asks if there was anything else unusual, and Brock mentions the temperature drop.
At the cell, Dean scans for EMF but picks up nothing. The Winchesters figure they're dealing with ghost possessions and the spirit is attached to the masks. The brothers say that iron and salt should repel the ghost, and Donna takes a salt container out of her diet pack. Dean shoots the mascot with a shotgun full of salt pellets, and the ghost flies out of the cell. The mask falls off, revealing a girl, Michelle. They take her out and the Winchesters points out that no one saw the girl's face. They suggest that Donna report that a drifter was wearing the mask and overpowered Donna. They question Michelle and she explains that she picked up the new mascot costume and tried it on. Rita Johnson donated the costume to the school.
The next day, Donna and the brothers visit Donna and her son Max. Donna takes Max to the police car to distract him. Rita explains that the costumes belonged to her brother Chester, who was a kids' party performer before he died. She has a photo of Chester dressed as a clown, and Sam hastily pushes it away. Chester suffered from depression and took his own life by jumping off a bridge. Max begged Rita to keep the costumes because he loved his uncle, and Rita finally donated them to local schools and the thrift shop. She confirms that Chester was cremated, and Sam asks for a list of the costumes. Dean asks if Chester had any unfinished business with anyone, and Rita says that Chester didn't know the victims.
Outside, Sam and Dean tell Donna what they've learned. They figure that they have to burn the costumes to stop Chester's ghost. Donna tells them that she's already had Doug collect the costumes at the high school, and the brothers give her a list of the other costumes. Dean explains that ghosts typically come back for revenge, and Sam goes to check on Evans while Dean looks for Fran.
At the hospital, a masked clown enters Evans' room. He takes out a scalpel and cuts Evans' throat. As the clown walks down the hallway afterward, carrying the bloody scalpel, and takes the elevator. Sam is inside and stares at the clown in terror. The clown turns to Sam and stares at him, and Sam notices the scalpel. He grabs the clown and disarms him, and they fight. The clown chokes Sam, who jams a bar of iron into his side. The ghost flies out through the vent, and Sam removes the mask to reveal a confused old man.
Donna arrives at the hospital and Sam gives her the mask. He explains that the old man is Steve Burgess, a retired GP. He was playing dress-up with his grandson and blacked out. Sam let him "escape" like Mitchell. Doug comes in and Donna insists that it's another copycat killer. He goes to get a woodpecker costume, and Sam wonders why she isn't giving Doug a break. He suggests that Donna isn't giving Doug a chance, and she tells Sam to mind his own business.
Dean meets with Fran, who says that Stan and Evans were college roommates and as close as brothers. She refuses to say Chester's name, saying that he makes her sick. As Dean leaves, he checks in with Sam. He's learned that Evans and Stan accused Chester of being a pedophile. Rather than embarrass the children, they tracked down Chester and met Rita. They gave her their accusations, she told Chester, and he killed himself... apparently.
That night, Dean goes to Rita's house and Max answers the door. The boy says that Rita is out and invites Dean to wait inside. There's a deck of cards on the table, and Max explains that he was practicing a magic trick. He admits that he misses his uncle, and insists that what the men said about Chester wasn't true. Rita comes in with Sam and angrily insists that she told them everything she knows. She sends Max to his room and Sam says that they know Evans and Stan confronted her about Chester. He figures that Chester is connected to the murders and asks for the truth. Dean warns that her life and Max's may be at risk, and Rita explains about the two men's accusations. She told them to go to the cops, but they didn't have any evidence. Then Rita worried that it was true, and figured she couldn't see Chester for what he really was. She wondered if Chester was hurting Max, and called Stan back. Stan said that he and evans would take care of it.
Chester leaves work in a deer costume, and Stan and Evans confront him. They drag him away.
The two men promised Rita that they would just scare Chester, and she thought that might stop him.
The two men dangle Chester off of a bridge and Chester struggles. Stan and Evans lose their grip and Chester falls to his death.
Evans and Stan told Rita that it was an accident. She wanted to go to the police, but Stan warned that they'd go to jail and Rita didn't want Max to lose his mother as well as his uncle and father. Donna calls Sam and tells him that she and Doug have found and burned all of the costumes on the list... except for the deer costume, which isn't on the list.
Max enters the living room wearing the deer mask and knocks Dean across the room. Sam tries to use the iron on him but the possessed Max sends him flying as well. As Max chokes Rita, Dean wakes up, grabs the iron, and rams it into Max's side. The ghost leaves and the mask falls off. Sam wakes up and Dean tosses the map to him. Outside, Sam gets the gasoline from the trunk, while Dean goes through the cupboards and gets a container of salt.
Chester materializes and knocks Sam unconscious.
Dean draws a circle of salt around Rita and Max, just as Chester arrives. He knocks Dean away and Max calls to his uncle.
Sam wakes up and sees the mask.
Chester hesitates and then grabs Dean and chokes him.
Sam sets the deer mask on fire.
Chester's spirit bursts into flames and disappears.
Later, Donna and Doug arrive at the house. Donna says goodbye to the brothers and figures that their lives are lousy. They says that she's earned the title of hunter and Donna hugs them. Once they leave, Donna tells Doug that he's been great and apologizes for being tough on him. Doug says that he understands because he's got baggage just like everyone else.
As the brothers head home, Sam explains that the keeps praying because he doesn't know what to do with the visions that God is giving him. He figures that it's about Lucifer's cage, and wonders if he has to go back there to get the answer to beat the Darkness. Dean warns that anything having to do with the cage is suicide and refuses to let it happen. Sam hesitantly agrees and they drive on.
Written by Gadfly on Nov 19, 2015