She is portrayed by Sunny May Allison.
|“||You are so fucking ugly.||„|
|~ Patriot, noting Shelly's symtoms|
Shelly attended Fort Chicken Elementary School on Monday. Prior to being infected, she ordered chicken nuggets at the school cafeteria, unknowingly being served a contaminated chicken nugget. Shelly obliviously consumed the infected nugget, resulting in her being infected by the food-borne virus.
Shelly, while attending substitute teacher Clint Hadson's fourth grade classroom, began to show symptoms of the virus, including blisters on her face. This led to her being tormented by her two classmates, Patriot and Dink, though she didn't respond to their insults. When Clint arrived and introduced himself to his students, Shelly appeared amused by Clint and Patriot's bickering. Shortly afterwards, Patriot resumed his torment of Shelly, culminating in him tearing off one of Shelly's pigtails. Enraged, Shelly attacked Patriot and bit a chunk of his face off, infecting him with the virus. Clint made an attempt to restrain her, but Shelly clawed his arm and fled outside the building.
Spreading the Virus
|“||"They got cooties. That's what they're always saying that girl Shelly has. Cooties. She's dirty.||„|
|~ Calvin, about Shelly|
Later on, during recess, Shelly's infection overcame her and she began to dig under the fence in the hopes of making an exit from the school. She was distracted when Dink confronted her on attacking Patriot. Shelly's response was to claw his face, infecting him with the virus. Shelly sent Dink off to infect the rest of the school while she resumed digging an exit under the fence. During this, Dink infected the other children, who attacked the school staff and brutally began to kill them off. Some of the staff, as well as one of Shelly's classmates, Calvin, managed to escape the carnage and hid away in the school.
During the chaos, a policeman was called to the school, where he attempted to investigate, unaware of the children's state. After the children mangled his fingers, he attempted to flee, but Shelly, who had successfully dug a hole out of school grounds, entered the officer's van and proceeded to kill him.
Shelly returned to the school, where she discovered the remaining staff and Calvin hiding. She was unable to enter the room, though, and engaged in a standoff with Doug, one of the school teachers. During this, Calvin explained that Shelly had "cooties". Clint, who had earlier been scratched by Shelly, began to experience stomach pain from the infection, but didn't turn feral, leading Doug to conclude that the virus only infected the pre-pubescent. Shelly eventually became disinterested and left, with Doug concluding that she had decided to commit murder somewhere else. Shelly proceeded to leave school grounds and left towards the nearby town of Danville, leaving the staff to her schoolmates.
|“||Nap time, mother-fuckers.||„|
|~ Wade to Shelly and the other kids|
At Danville, Shelly joined the infected children in the town in slaughtering the adults in the city. Along with a horde of other infected children, Shelly hid within a building which had been the site of a child's birthday party. During this, the school staff and the uninfected children arrived in the town and hid within the building. Once inside, Shelly and the other children revealed themselves to their enemies, surrounding them. Shelly cackled as the children surrounded their victims, but Wade, who had previously been thought dead, unexpectedly arrived. Shelly immediately pursued the staff as they fled to crossing guard Rick's van. Clint and Wade blocked the children with a large balloon ball, but Shelly began to squeeze through. Before she could escape, Wade dowsed her and the other children with gasoline. As Shelly hurriedly attempted to escape, Wade lit her and the other children aflame before retreating in the van. Shelly, her body aflame, briefly pursued them, but she soon succumbed to her wounds and fell over, dead.
Little is known of Shelly's personality prior to her infection. Presumably, she was somewhat quiet, as she never spoke. When her classmates mocked Shelly for her blisters, Shelly, while appearing uncomfortable with the insults, didn't say anything. When Clint introduced himself to the class, Shelly grinned, assumedly finding Clint amusing.
Post-infected, Shelly was shown to be very feral and aggressive. Similar to the other infected children, Shelly's behavior seemed to stem from her childlike impulses being amplified by the virus. She appeared to have a level of intelligence even while infected, as she managed to make an exit out of school grounds under the fence, and successfully ambushed a police officer by hiding in his car. She also managed to direct herself through a forest and into Danville.
Shelly has pale skin, blue eyes, and blonde hair. She had painted pink fingernails. After being infected, Shelly gained noticeable eye bags and a series of blisters on her face, as well as visible phlegm. As time goes on, the blisters spread across her mouth and cheeks, and her skin decays.
She wore her hair in twin pigtails, but one of them was torn off by Patriot. In Danville, Shelly's face was covered in blood, suggesting she had killed more people in the town.
- Shelly never speaks throughout the film.
- It is unknown how Shelly got to Danville. Presumably, she trekked there in the afternoon, as it was nighttime when the staff arrived in the town.
- Oddly, Shelly's name is pronounced "Shelley" on the end credits.