She is first seen when Ash unsuccessfully tried to flirt with her, only for her to twist his arm and threaten him. Later she gets a video call from her father, telling her that her mother, Suzy has come home, Kelly is disturbed by this due to her mother, having died in a car accident six months prior. Pablo offers to take her to her parents only for him to take her to Ash who she is not happy to see. Pablo attempts to convince Ash to help them moments before Kelly gets attacked by a possessed gardener. Ash saves her by throwing an axe at the Deadite, and his trailer is then attacked by a Kandarian Demon. Kelly screams for it to leave them alone, the attack suddenly stops and Pablo enquires if it will get in, Ash confirms that it will and readies himself for the attack, taking Kelly's belt to strap his gun holster to him and then using his shotgun to kill the deadite. Kelly asks him to help her father but Ash refuses, telling her that the entire world is at stake. Ash opens a curtain to get his chainsaw only to see a possessed Vivian waiting for him. After a short battle in which Kelly is nearly killed, Ash slays Vivian.
Kelly leaves for her parent's home, Ash follows her believing that she stole the Necronomicon when in fact Pablo did in order to trick Ash into helping Kelly. Ash arrives at Kelly's home to find Suzy seemingly alive but makes it clear that he believes she is a Deadite, a belief that is proven correct after he punches her. The possessed Suzy kills Kelly's father and attempts to trick Kelly by assuming her human form, but Ash mananges to kill the Deadite. He buries the dead and puts a cross on the graves, only for Kelly to point out that they were Jewish and Ash tells that she should have said that in the first place.
Later, the group arrives at the Books From Beyond store where Ash plans on getting the book translated to stop the Kandarian demon and its Deadites. Kelly is tasked with watching Amanda Fisher, a cop who has been trying to catch Ash and had just moments ago had him at gunpoint. Amanda tricks Kelly into letting her go and comes across Ash and the demon he has summoned. After a brutal fight that resulted in the death of the shop owner, Kelly seemingly vanquishes Eligos.
On their way to meet Pablo's uncle, a shaman known as El Brujo, Kelly begins to fall ill, experience vomiting and headaches. After a particularly painful headache it is revealed that she has actually been possessed by Eligos. The possessed Kelly then proceeds to electrocute Pablo to distract El Brujo to enter Ash's mind, hijacking his "trip" and turning it into a nightmare that threatens his life.
After a momentarily possessed Ash attempts to strangle Kelly (as a ruse by Eligos to frame Ash), he is restrained and gagged and El Brujo begins to perform various exorcism rites on him (Ash, all while, exasperatingly trying to expose Kelly's possession). Meanwhile, a still yet secretly possessed Kelly tries to seduce and kill Pablo. After multiple failed attempts, Eligos drops all deception and attacks in full possessed form. Kelly is then restrained by the group and El Brujo begins her exorcism. When the exorcism fails, Pablo draws Eligos out of Kelly's body by offering himself as a "willing host", which ultimately led El Brujo's death and Eligos destroyed by Ash.
Kelly's possession and near-death at the hands of Eligos left her with strengthened resolve and further fueled her hatred of the Deadites. During a Deadite attack at the Western Moose, Kelly took it upon herself to slay a Deadite waitress in brutal fashion, Ash commenting, "I think she needed that".
Kelly's personality can be described as no-nonsense, aggressive and sarcastic. Kelly enjoys killing deadites and using guns to destroy them, initially favoring an M16 rifle before later using an MP5 sub-machine gun. She is often described (by Ash and those related to Ash, i.e. Brock Williams and the Ashy Slashy puppet) as being "filthy and fine".
"Back off now or I will fuck, your faces, with bullets!"
"Now there's my powerful vagina"