The agents investigate the murder of a teenager who died after insects devoured his brain.
Using a video camera, David Winkle, aka Sky Commander Winky, photographs a series of ridiculous stunts with the assistance of his friend, Bill Kizzler, aka Cap�n Dare. The pair plan to broadcast the footage on a cable 'reality' program known as 'The Dumb Ass Show.' A group of other teenagers watch the proceedings. Among them are a pretty girl, Natalie Gordon, and a boy, Dylan Lokensgard.
Eventually, David and Bill prepare to videotape the climatic stunt, one involving a shopping cart and some fireworks. But the stunt goes awry and Cap�n Dare is thrown to the ground. Natalie and Winky run to the boy�s side, but when they pull off his protective helmet, are shocked to discover that the boy�s head has collapsed inward like a deflated basketball.
A local medical examiner, Dr. Fountain, contacts the FBI for assistance. As Reyes and Doggett observe, the dead boy�s eyelids begin moving. Using a pair of forceps, Reyes lifts one of the eyelids. Suddenly, a swarm of buzzing blow flies emerges from the socket.
A short time later, Scully arrives at the scene. After examining the victim, she concludes that his insides were devoured by hungry insects, explaining why his skull collapsed from the inside. But she is at a loss to explain why it happened. Later, Dr. Rocky Bronzino, a field entomological expert, joins the investigation.
Meanwhile, inside the school cafeteria, Winky picks a fight with Dylan and splatters pie on his head. Dylan�s mother, who works at the school as an administrator, calls Winky into her office. When Winky enters, he�s greeted by Reyes and Doggett, who question him about events leading up to Bill Kizzler�s death. Shortly thereafter, Winky freaks out when the words 'dumb ass' appear on his back in bloody red welts. The agents are unsure how to respond.
Meanwhile, Dylan retires to his bedroom and blasts some music on his stereo. Suddenly, a swarm of beetles crawl into his room.
Scully calles Reyes and Doggett into an autopsy bay, where she explains that Bronzino discovered that the insects which ate Bill Kizzler�s brain were all female, suggesting that something biological or hormonal was related to the attack. Reyes believes that someone is manipulating bugs and using them as a method of carrying out murder.
Natalie tells Dylan that she�s sorry about what Winky did to him inside the cafeteria. They reminisce about simpler times. Dylan is very attracted to Natalie but cannot express his feelings.
A short time later, the agents approach Dylan and question him about Bill Kizzler�s death. Dylan grows nervous and begins to sweat. Dylan wipes the perspiration away with a Kleenex. Mrs. Lokensgard interrupts the meeting and insists her son is innocent of wrongdoing. Moments later, bugs swarm Dylan and cover his entire body. By the time an emergency team reaches the school, the insects have all disappeared. Reyes then informs Doggett that the boy is unharmed. Mrs. Lokensgard escorts her son home.
Reyes gives Scully and Bronzino the Kleenex that Dylan used during the interrogation. Bronzino�s pheromone-detecting device picks up an overwhelming amount of insect pheromone on the tissue. Scully hypothesizes that the pubescent Dylan�s body chemistry has gone awry. But Reyes believes that Dylan is not only attracting the bugs, he�s manipulating them for his own purposes.
Meanwhile, Natalie sneaks into Dylan�s bedroom, where the two kiss. The pair then French kiss... and Natalie reacts with horror when she discovers blood coming from her mouth. When Natalie runs off, Dylan gives chase, but he soon runs into Winky and his cohorts. Dylan is forced into the group�s car. He soon surprises everyone when a set of bug mandibles shoot out of his mouth, followed by a spray of webbing. The car goes out of control and crashes.
Doggett finds the overturned car and rescues Winky and his buddies, who are encased in spider webbing. When word of Dylan�s rampage reaches Scully, she heads off to find him, leaving Bronzino alone in the Lokensgard house. Shortly thereafter, Bronzino is attacked by Mrs. Lokensgard, who has her own set of insect mandibles.
Meanwhile, Reyes locates Natalie at Natalie�s house. But Dylan also shows up, threatening to do Reyes harm unless she lets Natalie leave with him. Realising that Reyes will draw her weapon, Natalie stands between the pair and defuses the situation. She then walks off with Dylan. A short time later, Doggett finds Reyes inside Natalie�s house, her body covered with webbing.
Scully returns to the Lokensgard house, where she finds Bronzino in the attic, his body encased in webbing. Scully tears it away and sets Bronzino free. When Scully later files her report, she notes Bronzino�s conclusion that Mrs. Lokensgard was neither human nor insect, but something in between. Mrs. Lokensgard and her son flee the area.
Later, Natalie looks out her window and sees fireflies dancing in the night air. The fireflies then spell out the words, 'I love you.'