Ashley Joanna Williams is the main character in the Evil Dead series.
Biography
Early Life
Ash was in his twenties when he lived a "normal" life. He was employed at the superstore, S-Mart (where he worked in the housewares department), and had a girlfriend, Linda. Based on the engineering textbooks in the trunk of his car, it appears that he was studying at Michigan State University. Also, in the first Army Of Darkness comic book released by Dark Horse in 1992, Ash says his father blew $20,000 on his engineering degree showing that either he completed his schooling and had done nothing with his education, or dropped out. (With his ability to easily improvise devices, this implies that he at least excels in the area, if not actually possessing that degree.)
The Cabin (The First Night)
In The Evil Dead, Ash and his girlfriend Linda, sister Cheryl, and friends Scotty and Shelly stay at a log cabin in the woods, where they find the "Naturon Demonto" (renamed or possibly translated to Necronomicon Ex-Mortis in the sequels), the "Book of the Dead", along with a tape recorder. The tape is a recording of the owner of the cabin, who was translating a passage of the book. By playing the tape, Ash and his friends awake the evil spirits who can now possess the living. Ash's friends and sister are consequently possessed and killed one by one, until he's the last survivor. He finally destroys the Necronomicon by throwing it in the fireplace, and in doing so causes the possessed bodies of Scotty and Cheryl to rapidly decay and 'die', and the evil seems to be driven back. However, the film ends with Ash being attacked or possibly overtaken by an evil spirit himself.
The Second Night
Evil Dead II continues the story from the previous film after a stunted recap in which the audience is only introduced to Ash's girlfriend Linda (who still subsequently gets possessed, decapitated and buried) and Ash himself, to the point where the evil spirit attacks Ash. From this point, the film continues the story from where the first film left off. Carried a good distance by the demon, Ash is slammed hard against a tree and falls in a puddle of water. From here he becomes a deadite but shortly afterwards is released from the spirit by the coming of dawn, only to pass out. Ash regains consciousness moments before sunset. Deciding to get out of there as fast as he can, he climbs into his car and drives to where the bridge was, only to find it completely destroyed by the evil force. As the sun quickly sets, said force starts climbing up the cliff, and Ash hops into his car, driving away as fast as he can and as a result, crashing right into a treestump that sends him flying through the windshield. With the evil close behind him, he runs into the cabin and through it trying to hide, and ducks into the trapdoor, waiting until the evil force leaves. After it does, Ash comes out, only to find himself stuck at the cabin with the spirits of the Evil Dead for yet another night. Later, the cabin owner's daughter, Annie and three more people arrive. It is near the end of this film that Ash gets his famous chainsaw in place of his right hand. The film ends with Ash being sucked into a vortex and traveling back in time to 1300 AD, where the locals claim, according to their prophecies, that he is "The Hero From The Sky" who will save them from the Deadites (demon-possessed zombies).
Back In Time
The next film continues the story from there (though he receives far less of a warm welcome than the end of the previous film suggests). Ash has to defeat his alter-ego known as "Bad Ash"/"Evil Ash" who is leading the Army of Darkness to steal the Necronomicon. In this movie, Ash constructs a mechanical prosthetic hand out of a gauntlet from a suit of armor, using it throughout the film in place of the chainsaw (though he still carries it with him). The movie has two different endings, one where he returns to his own time and defends S-Mart from a possessed woman, and another, the director's cut (or Japanese version entitled "Captain Supermarket"), where he ends up in a post-apocalyptic future.
Television Series: Ash Vs. Evil Dead
Season 1:
30 years after returning from 1300 AD, Ash, now living in a trailer park, has been in hiding from the evil of the world, living a reckless life full of pot-smoking and prostitutes. One night while high, Ash reads from the Necronomicon, causing the evil to be unleashed on the world once more. Ash came out of hiding and recruited fellow Value Stop employees Pablo and Kelly to help him find a way to stop the evil once and for all. In the end, Ash's journey to stop the evil led him back to the cabin where everything started, and it was also where he was confronted by Ruby Knowby, the daughter of the professor who brought the Necronomicon to the cabin all those years ago. Ruby demanded Ash give her the book and promised him that she could stop the evil from returning permanently, and when Ash gave her the book, she reveled her true self: one of The Dark Ones, specifically the one who wrote the Necronomicon. Ash was given two options by Ruby, kill her and the evil will be gone for good, or let her live and Ash can live peacefully in Jacksonville, Florida while she unleashed all of the evil the book contained. Ash chose the easy way out and took the offer for Jacksonville, causing the world to be overrun with evil.
Season 2:
The second season roars back into action with Ash leaving his beloved Jacksonville and returning to his hometown of Elk Grove. There, he confronts Ruby, who now possesses the powerful Necronomicon. The former enemies have to form an uneasy alliance as Elk Grove soon becomes the nucleus of evil.
Evil Ash
Evil Ash is Ash Williams's dark side, and is also implied to be the evil force from the film's predecessors, which was sent back through the time rift moments before Ash was.
An unseen evil force, he chased Ash through the forest (similar to the first two films) as he was on his way to get the Necronomicon from the cemetery. He chased him into a windmill and entered the mirror. When Ash smashed the mirror, it took the form of several Tiny Ashes, which tortured him until one jumped down his throat, and the others ran off and disappeared. Manifesting into his dark side, the Tiny Ash separated from Ash, as his evil clone, Evil Ash. Ash shot him in the head with his shotgun and dismembered him with his chainsaw, and the buried him. His head survived long enough to taunt Ash more.
When Ash retrieved the Necronomicon, he was supposed to speak the words "Klaatu Verata Nikto", but forgot what the word "Nikto" was, and said it wrong, coughing so it sounded like he said it. This raised an army of the dead, and Evil Ash was reawakened as a Deadite. The leader of the Deadite army, he kidnapped Sheila and led the Deadite army to get the Necronomicon. Initially reluctant, Ash decided to lead Arthur's army into battle against the Deadite army. Ash fought Evil Ash and set him on fire, turning him into a skeleton. He attacked Ash one more time, but when he unwittingly jumped onto a catapult with a bag of gunpowder whose fuse was ignited by Ash's torch, Ash activated the catapult to send Evil Ash flying into the air with the bag of gunpowder, which exploded and completely destroyed him.
Without their leader, the remaining Deadites were forced to retreat.