The game takes place eight years after the events of the Army of Darkness. After regaining his job at S-Mart and beginning a new relationship with fellow employee Jenny, Ashley “Ash” Williams begins suffering from recurring nightmares about the Necronomicon and the Deadites, which haunt him for years. Wanting to help him, Jenny decides to take Ash back to Professor Knowby’s old cabin to help him face his demons.
However, shortly after arriving, Ash’s possessed severed hand appears and plays Knowby’s old cassette containing the Necronomicon’s incantation once again. Despite Ash’s attempts to stop it, the evil once again awakens in the woods, smashing through the window and kidnapping Jenny. When Ash goes to grab an axe above the mirror, his evil twin, Bad Ash exits the mirror and knocks him unconscious. After awakening, Ash quickly goes out to the workshed and reassembles his chainsaw-hand before going out to stop the Necronomicon and save Jenny.
After reading some of Professor Knowby’s notes, Ash learns of a priest named Father Allard, whom Knowby was working with to decipher the Necronomicon and send the evil back to where it came. Upon consulting Father Allard at his church, Ash departs to gather the five missing pages from the Necronomicon and the Kandarian Dagger, the latter of which he obtains from a possessed Annie Knowby in the cabin’s fruit cellar. After the two come across a possessed Jenny, Father Allard uses the pages and the dagger to create a portal and exorcise the demons from Jenny’s body. However, Allard then reveals himself to be Bad Ash in disguise, who promptly kidnaps Jenny and jumps into the portal with Ash in hot pursuit, the two arriving in an Arabian village in the 9th century.
Ash finally catches up with Bad Ash, who intends to let Jenny be consumed by the Dark Ones and cross over into this world while Bad Ash will kill Ash and use him as a ‘calling card’. The two fight, with Bad Ash transforming into a giant scorpion-like deadite. Nonetheless, Ash still defeats him and manages to use the pages of the Necronomicon to pull Bad Ash into the portal. With Jenny now free from possession, Ash uses another of the spells to open a portal and send them back home.
Upon arriving, Ash and Jenny discover to their horror that they’ve arrived in a version of Dearborn, Michigan that is ruled by the Dark Ones. Seeing several various Necronomicon books in a shop window, Ash screams as the game ends.