An abandoned power plant in Norway houses an ILLEGAL BLACK METAL CONCERT. Inside, sparks fly, music assaults the senses, Zombies rock out. A skeleton fastened to a gothic cross hangs above the stage. Without warning, a Delta Unit bursts in and makes way for DR. SOLBERG, a kind of Norwegian Brennan, to get a closer look at the skeleton. She confirms it's human and American. The Norwegians want no part of this and send it back where it came from.
At the lab, CAM explains that the victim's skeleton was used as a stage prop. It was stolen from an American Death metal band in DC six months ago and brought to Norway. BRENNAN deduces that the skeleton belongs to a teenage male. CLARK EDISON notes there is staining on the skull. The victim's ribs have been severed at the spine and spread to resemble wings. Brennan reports that this is known as the Blood Eagle. Fortunately, this ancient form of torture occurred post-mortem. One question remains: is this murder or a grave robbery?
At the FBI, BOOTH instructs an assistant to research the metal music scene in DC. GORDON WYATT appears and, because he has a musical background, makes Booth aware that there is more than one type of metal. Wyatt is in town to be interviewed for Sweets' book about Booth and Brennan's working relationship. Wyatt offers to barbeque for Booth but Booth insists he is the expert on barbequing. Wyatt believes his culinary skills have improved.
In the lab, Angela shows Cam a rendering of the victim. He is a large, pale boy whom Angela refers to as "puppy." Cam found no embalming fluid on the victim. He was never buried in a sanctioned grave. All signs point to murder.
At the FBI, SWEETS is thrilled to meet Wyatt. Wyatt compliments Sweets on his manuscript about opposite personalities working toward a common goal. However, he doesn't believe Booth and Brennan are opposites. Sweets is taken aback and asks for Wyatt's opinion on Booth and Brennan's sexual attraction to each other. Sweets is of the mindset that they have pushed their attraction aside in favor of a working relationship. Wyatt believes one of the partners is aware of the attraction and struggles with it daily. Again, Sweets is surprised. He wants to speak further but Wyatt wouldn't dare influence Sweets' book. Sweets wishes he would. He wants Wyatt to write the introduction. Wyatt refuses. He is retiring.
At the lab, HODGINS and Cam watch as Angela rocks out to metal music in her office. Hodgins determined that the skull was stained with makeup. The victim was wearing it when he died and it seeped into the skull. Based on the stains, Angela reconstructed the victim's appearance with the makeup. She did a search of metal web pages and came up with a match. The victim, known as MAYHEM, was in a band called Spew.
At the diner, Sweets informs Booth and Brennan that Wyatt is retiring. Brennan supports the decision, believing Wyatt's intellect could be put towards something more useful. Booth takes a call from Cam. He learns they need to track down a Death metal band named Spew. The band is underground so it may be difficult. Sweets explains the difference between Death metal and Black metal to the partners. Apparently, he was into Death metal as a teenager.
At the lab, Brennan, Hodgins and Cam work on locating the band through particulates. This is their only option since concerts are given at secret locations and select people invited. Hodgins reports there was dried mud on the boots duct taped to the victim. The mud contained Mad Cow disease. Perhaps the concerts take place at a local condemned slaughterhouse. Brennan indicates they don't know if the boots belonged to the victim.
In the Bone Room, Clark tells Brennan that the victim wore size eleven shoes. The boots are size eleven. Additionally, the victim was missing a toe. The boots are worn in a way that suggests the wearer only had four toes one of their feet. Brennan is satisfied. Where is that slaughterhouse again?
Booth drives to the slaughterhouse with Brennan and Wyatt. Booth asked Wyatt to come because they need his expertise. Brennan reveals the truth: Booth wants to convince him not to retire. Wyatt believes his expertise in rock music, not in psychiatry, can be useful. He was the founding member of a proto-glam rock outfit. Booth puts two and two together. Gordon Wyatt was Noddy Comet. Brennan isn't familiar with the name but Booth listened to Wyatt's records.
At the slaughterhouse, the group finds Spew practicing. Their music is not pleasing to the ears though Wyatt appreciates the guitar. Booth flashes his badge and asks the band to shut down. PINWORM spits at Booth's badge so Booth fires his gun into the amplifier. The band is momentarily stunned, as are Brennan and Wyatt.
At the FBI, Booth is on desk duty. He fired his weapon and has to wait until the paperwork clears. He watches from his laptop as Brennan and Sweets question MONTY BIGELOW, MATT STICKNEY and DARREL MOSS, the members of Spew. The band contends that Mayhem was a dabbler. They won't give up his legal name until Sweets offers to charge them with assaulting a Federal Agent. Matt Stickney, also called Pinworm, allows Darrel, also known as GRINDER, to tell Sweets that Mayhem's name is JUSTIN DANCY. They last saw him a year ago when he quit the band. Sweets has a realization and leaves.
In Booth's Office, Booth hides his laptop before Sweets enters. Sweets reports that Darrel's body language betrays an emotional connection to the victim. Sweets wants him "cleaned up" so he and Wyatt can question him alone.
At the lab, Cam and Clark work with the victim's bones and X-rays. Clark has discovered damage to the pelvic bone. There are gouge marks and what appears to be a bullet wound. The victim was shot. The wound healed and someone dug the bullet out of the victim's backside.
At the FBI, Wyatt and Sweets question Darrel Moss. He has been forcibly cleaned, given a haircut and put in an orange jumpsuit. Not quite the menacing person he once was, Sweets tells Darrel they know he replaced Mayhem in the band. Wyatt produces a photograph of a young Darrel with his childhood friend, Justin Dancy. The picture is enough to make Darrel talk. A deathcore band named Zorch used Mayhem as a prop before the Norwegians.
Brennan takes a trip to Morgue, an underground club where Zorch performs. Sweets accompanies her, dressed in deathcore attire in order to "meld." He knows that the lead singer of Zorch is MURDERBREATH. Zorch and Spew are rivals. Their fans often attack each other. Brennan and Sweets see that Murderbreath has a knife. As the crowd chants, Murderbreath slits his throat. Sweets assures Brennan that this is purely theatrical. Murderbreath is not actually harming himself. After a moment, Murderbreath sinks to the ground, bleeding profusely. Brennan and Sweets rush to the stage. Brennan rips off Sweets' shirt to use as a compress. She notices scars on Sweets' back as she calls for an ambulance.
At the FBI, Brennan and Sweets deal with a bandaged Murderbreath. Someone switched his prop knife for a real one but he doesn't care. Once word gets out that he nearly died, he'll be a legend. Brennan wants to know about the rivalry with Spew. Did it go so far that he killed their bassist? Murderbreath is happy to take credit for what happened to Mayhem but not after Brennan plays bad cop, threatening him with prison, death row, execution and an end to his concerts. Murderbreath heard a rumor about where Mayhem's bones were buried. He found the bones, dug them up, stole the cross and made the Blood Eagle but he didn't kill Mayhem.
At the diner, Wyatt declares Booth fit for duty. Booth wonders what Wyatt will do now and Wyatt confides that he is attending the Institute of Culinary Arts. Brennan is distracted by the case. The suspects turn the notion of community on its head. Wyatt observes that they still create music, no matter how destructive they seem. Sweets was one of them and he has become a productive member of society. Wyatt has learned that Sweets is interested in Booth and Brennan's childhoods from his manuscript. Brennan remembers that she saw scars on Sweets' back. It looked as though he'd been whipped.
At the lab, Angela informs the gang that Mayhem was "shot" at over sixty concerts. There are multiple cell phones videos of this popular set piece online. A girl appears, aims a gun, shoots and Mayhem "spews" blood from his throat. In one video, the bullet passes through the victim's guitar, not his throat. Mayhem falls to the ground. This bullet was real. Angela combines images of the girl to construct a face. Hopefully, they can ID the mystery shooter.
At the FBI, Booth faces LEXIE, the one named power punk wonder. Lexie used to be in the Death metal scene but has recently gone more mainstream. She claims that someone replaced the blanks with real bullets. It wasn't her fault that Mayhem got shot. Booth knows better. She knew the bullet was real or she would have aimed for this throat like every other time. Lexie admits that the gunshot was planned but it was Justin's idea. He wanted to prove how hardcore he was. Booth tells her that Justin is dead. Lexie can't believe it. She implores Booth to catch the criminal. She confesses that Justin wanted to leave Death metal and join her band. Someone in Spew must have found out or maybe it was a crazy fan but a metal fanatic definitely killed him.
At the lab, Brennan and Clark determine cause of death. Brennan notices something about the victim's greenstick fractures. She asks Clark to get on all fours. Clark reluctantly plays along. Brennan approaches with an electrical cord and loops it around his neck. She then drives her knee into Clark's back. Inward bowing and incomplete fractures suggest this is what happened to the victim. Clark stands and dusts himself off, wondering about the stab wounds to the C5. Brennan has a theory: it wasn't a stab wound. The victim was strangled with barbed wire.
In Brennan's Office, Sweets discusses motive with the partners. He confirms that Mayhem could have been killed for leaving the band. Wyatt and Sweets believe the murderer will have a souvenir from the crime. It's his way of bragging. Booth recalls that a bullet was gouged from the victim's behind. Everyone agrees this could be the souvenir claimed by the murderer. Booth produces a photograph of Pinworm. He wears a bullet around his neck.
At the FBI, Pinworm sketches while waiting for Booth and Brennan. As they make their way to the Interrogation Room, Sweets confronts Wyatt about his career change. Wyatt surmises that Sweets was adopted as a young child by an older couple, a pair that rescued him. Sweets does not disagree. He adds that his adoptive parents both died before he came to work with Booth and Brennan. Wyatt explains that Sweets' parents saved him and so he believes that others can be saved. Wyatt does not share the same view.
In the Interrogation Room, Pinworm doesn't remember where he got the bullet. He gives Brennan his sketch. It is a drawing of her as a metal goddess, wrapped in barbed wire. He claims that no member of Spew would leave to be with Lexie. Spew is the real thing. Their music comes from hell. Whatever Brennan and Booth may have seen doesn't come close to what happens in Pinworm's mind. Wyatt and Sweets realize that Pinworm enjoys the attention from Brennan and Booth. He needs an audience. Without one, he has nothing. Wyatt gives the tip to Booth. Booth pretends that Murderbreath confessed to the murder. Pinworm can go. He won't get credit for anything. This incites Pinworm. He rants that Murderbreath couldn't kill anyone. He isn't heavy enough to strangle someone with barbed wire. Pinworm just made his confession.
At Booth's Apartment, Wyatt prepares a meal. Booth and Brennan thank him for his help with the case. Wyatt insists they should thank Sweets. He reveals that Sweets lost both of his parents before beginning work with them. He encourages them to show Sweets he is not the only one with scars.
Brennan and Booth find Sweets at the FBI. They invite him to dinner. Sweets refuses so Brennan improvises. She shares that her foster parents locked her in the trunk of a car for two days after she broke a dish. She also confesses that she knows about the scars on Sweets' back. Brennan encourages Booth to say something but he won't. Brennan gives him a pleading look and he manages to choke out one thing. "If it wasn't for my grandfather, I probably would've killed myself when I was a kid." Booth ensures Brennan is all right and Sweets finally understands Wyatt's observations. Brennan and Booth convince Sweets to come to dinner. The group moves off, leaving Sweets' manuscript behind. It is now entitled, "Bones: The Heart of the Matter."