The horror-comedy film begins with Ash Williams, the protagonist, narrating a manic and heavily edited summary of events from the first movie: he and his girlfriend are out for a romantic getaway in a secluded cabin in the woods. In the cabin Ash comes across a tape recorder containing spoken passages read from the Necronomicon Ex-Mortis, an ancient evil text containing all sorts of foul rituals unearthed during an archaeological dig. The invocation releases an evil being called the Kandarian Demon. It kills Linda, Ash’s girlfriend then possesses her remains turning her into an undead monster known as a “deadite.” The possessed Linda then proceeds to violently attack Ash. He reluctantly dispatches by lopping her head off with a shovel and buries her remains near the cabin.
Come morning, the now disembodied demon forcibly drags Ash through the woods surrounding the cabin momentarily gaining control over him. When the sun has fully risen though, the demon looses his hold over Ash and he regains his senses. After his encounter he tries to flee by car but discovers that the bridge connecting the cabin to the rest of the world has been ruined barring his escape. The demon then resumes tormenting Ash, hounding him back to the cabin. In the cabin he is attacked once more, this time by Linda’s severed head. In the ensuing fight his hand is bitten and to make matters worse Linda’s headless body has also been revived by the same malevolent power, attacking him with a chainsaw. Ash wins the fight over the re-animated body parts, destroying them completely to prevent them from returning. His right hand however, having been bitten, now falls under the control of the Kandarian Demon and begins attacking Ash, forcing him to sever his possessed limb.
The severed hand escapes and takes refuge in the walls of the cabin before Ash has a chance to mutilate it. The hand eventually escapes. During all the chaos Annie, Prof. Knowby’s daughter and Ed Getley, her colleague and fellow researcher, returns from their dig with the missing sections of the Necronomicon. A tangled network of metal that was once the bridge greets them, like Ash. The two recruit residents of the area, Bobby Joe and Jake, to help them navigate another route to the cabin. They arrive to see Ash on the brink of madness, having been tormented by the Kandarian for sometime now. The four meet Ash at the cabin and together listen to recordings of Prof. Knowby. In his recordings he narrates how Henrietta, his wife, was controlled by the demon, compelling her to kill him. Henrietta, now an undead monster like Linda was, is locked away at the cabin’s cellar. She eventually manages to break free and proceeds to assault and finally possess Ed. Ash dispatches the deadite Ed, mutilating him as he did the deadite Linda. Bobby Joe tries to flee but is captured by demonic animated trees to be torn to pieces.
Annie threatens to shoot Jake and Ash if they do not help in rescuing Bobby Joe; unfortunately though Ash falls under the demon’s thrall once again and he attacks Jake knocking him out. Annie takes shelter in the cabin but ends up unintentionally stabbing Jake, thinking that he was the demon-possessed Ash. A wounded Jake is finally brutally murdered by deadite Henrietta. A possessed Ash manages to come upon Annie intending to kill her but manages to snap out of the demon’s control when he sees Linda’s necklace.
Now that Ash has once again regained control of himself Annie assists him in combating the forces of evil, modifying the very chainsaw used to lop of his demon-possessed right hand to fit over his stump. The two make their way into the forest where they locate the other missing pages of the Necronomicon and destroy the monstrous creature that was once Henrietta. Upon defeating her though the other demonic forces inhabiting the woods begin to retaliate and it is revealed that Annie has only spoken half of the invocation for banishing the Kandarian. The forest dwelling demons double their efforts to thwart Annie as she begins chanting the second half of the spell but her efforts are halted and they discover that she has been stabbed in the back by Ash’s possessed severed right hand with a ritual dagger.
Annie falls over seemingly dead and Ash is accosted by the demons of the forest in an attempt to stop the ritual; Annie however manages to complete the incantation and a magical tempest/dimensional gate opens up sucking up the Kandarian, the forest demons, Ash’s Oldsmobile Delta 88, and finally Ash himself taking them all into the medieval past to the year 1300 AD. Annie dies from her injuries after having completed the rite. Ash on the other hand is met by a contingent of knights that erroneously think him to be a deadite. They gang up on him intending to kill him when a real a bat-winged deadite one shows up soon enough. Ash shoots it down with his shotgun and they welcome him as a savior; a matter that he responds to instead with agonized screaming.
