Ruby Knowby

Ruby is the main antagonist of Ash vs Evil Dead. Although "Ruby Knowby" is not her true name for it was merely a human disguise of this creature who in reality is one of the demonic extradimensiona beings known only as the Dark Ones and she is the true creator and author of the accursed spellbook known as the Necronomicon Ex-Mortis.

She is portrayed by Lucy Lawless of Xena: Warrior Princess fame.

Backstory
Ruby was once an overambitious member of the Dark Ones, a race of master demons who wreaked various havoc upon the human world through pestilence, wars, and many other diabolical activities. But Ruby, the most sinister member of Dark Ones, betrayed them, casting them off from the human world and sealed them to another dimension called Deadlands with the help of Kaya the necromancer who is a former member of Knights of Sumeria (an ancient anti-Deadite sect dedicated to protect humanity) who betrayed the sect. Not long after her treachery, her book Necronomicon Ex-Mortis, was stolen by the Knights of Sumeria, only to have the traitress Kaya to steal the evil book from the sect. Kaya, however, was destroyed by the Necronomicon and her soul trapped within the evil book.

After decimating the Knights to the brink of extinction, Ruby was sure that she annihilated them all (an assumption proved to be incorrect) and went to millennia of inactivity until the first episode of season 1 in Ash vs. Evil Dead. Ruby, under a human guise, resurfaced on Earth.

Taking an alias of Ruby Knowby and disguising as the alleged other daughter of Professor Raymond Knowby from Evil Dead 2. She has been searching for Ash Williams to take Necronomicon from him.

Season 1
Ruby briefly appeared in the series premiere "El Jefe", encountering detective Amanda Fisher after witnessing the demonic possession of her partner and having to kill him.

In "Brujo" Ruby saved Amanda from the demonically possessed Lionel, and then convinced Amanda that Ash was to blame for everything that has happened. She also convinced Amanda to help her hunt Ash down, and in the following episode "The Host", she revealed herself to be in possession of Ash's severed, possessed hand (which Ash cut off in Evil Dead 2), and was using it to track him down. They both arrive just a hair too late at the Brujo's ranch in "The Killer of Killers", which later saw Ruby engaged in a fight with the Brujo's charred skeleton, who tells Ruby that she will never have possession of the Necromicon. They both fell in the exploding pyre, but Ruby emerged unscathed in the following episode "Fire in the Hole".

Ruby finally finds Ash in the season's penultimate episode "Bound in Flesh", and confronts him by stating that she had been "cleaning up his mess." She shoots down Ash's plan to bury the Necromicon, stating that the book had to be destroyed. Back in the cabin where it all started, Ash defaces the cover of the book, and gives it to Ruby. However, Ruby opens the book and reads an incantation that will unleash all of the evil in the world, which included the face of the book attacking itself to Pablo's face. At that moment, Ruby reveals herself as the actual writer of the Necromicon, also revealing herself as a Dark One.

In the season finale "The Dark One", the evil Ruby attempts to convince Ash to give up his battle against evil, stating that she only wants to release all of the evil just to keep it under control. In return, she will give Ash what he's always wanted, a normal life and a peaceful retirement in Jacksonville. After Ash refuses, Ruby roars at him, flashing a pair of demonic black eyes while doing so, and Ash is transferred out of his fantasy scene in his trailer, and back in the real world in the cellar of the cabin. Ruby and Ash fight once again, with Ash set to kill Ruby with the Kandarian dagger, which was used to deface the book. At that moment, Ruby makes the same deal she made before, and this time, Ash accepts, to the dismay of Pablo (now free from Ruby's control) and Kelly. However, while Ash, Pablo, and Kelly are driving away, a sinkhole is formed; an indication that Ruby hasn't been true to her word.

Season 2
While it appears that Ruby seemingly betrayed Ash and co. the situation revealed to be more chaotic than it seemed: She now loses control over the Kandarian Demon (the ruthless dark spirit linked to the Necronomicon Ex-Mortis) and other lesser demons that she tried to summon Ash, but this inadvertently give away Ash's location to a pack of Deadites. There are two Rubys in season 2. One is on & off Ruby of the present who allies with Ash's group in her attempt to stop demon Baal and reclaim her control of Necronomicon, the other is Ruby of the past: pitiless, power-hungry and traitorous. At the season finale, Ruby of the present/the good Ruby sacrifices herself to stop Baal, but the Ruby of the past, her other evil self, still lives.

Season 3
Ruby (of the past) returns as an antagonist: once again in possession of the Necronomicon, she uses it along with her own supernatural power involving her own blood to produce her own demonic (and carnivorous) offspring who is revealed to be demonic version of Ash. Also Ruby disguises as a counselor named Rebecca Prevett for troubled teens to get to Brandy Barr, Ash William's long-lost daughter, in an attempt to have her turn against her father. Realizing that Brandy Barr is the child of Ash William, aka The Prophesied One, Ruby intends to ultimately kill Williams father and daughter and make her own demon child as the new Prophesied One. Ruby makes her move by commanding Deadites to destroy any possible offsprings Ash Williams may leave behind: She has her Deadites raid on a sperm bank where Ash had been frequented to destroy all Ash's sperms, depriving Ash of any more offsprings to continue on his legacy as Prophesied One.

While modern day Knights of Sumeria agents, the sect barely managed to survive against Ruby, was making contact with Ash and his gang, Ruby got a surprise visit from Kaya, her old partner in crime still being trapped within Necronomicon. Kaya warns the rift that was keeping Dark Ones imprisoned in Deadlands for millennia is becoming weaker and Dark Ones will soon be unleashed onto human world. Kaya pleads Ruby to free her before Dark Ones can discover her involvement with Ruby and Ruby vows to free her once she finds a suitable vessel. Realizing Ash's gang has Kandarian dagger and the sect which she once thought annihilated still exists, Ruby rushes to the site where the cabin was burnt down. There she finds Dalton, a KOS member and possessed, she de-possesses and tortures him for information. But Dalton commits suicide to avoid spilling everything and to avoid being re-possessed by his deadite: Ruby goes back empty-handed.

In episode 5 Baby Proof, Ash realizes that Ruby had been watching him from afar for decades. Unknown to her, Ash had broken into her hideout and after a gory slapstick fight manages to capture her demon child alive for him to prove to his daughter that Ash is serious about Ruby's true nature. But the evil child was a cunning one, and manages to deceive others when Ash presented the juvenile spawn, ending up convincing no one. Ruby first quickly secures her demon child, then tries to take Brandy into her custody and have Ash to be arrested but Brandy changes her mind at the last minute, fleeing with her father on Delta automobile.

While the demon child Ash-to-be goes into major metamorphosis Kelly Maxwell, a bellicose member of Ash's team who has had enough of being constantly threatened by evils and Ruby at the center of her troubles, snapped by the evils' attempt on Pablo's soul (another valuable member of Ash's team who was killed in season 2 but managed to resurrect to life) and goes to Ruby's hideout alone to have what was to be a final showdown. Initially Kelly had the upper hand in the mortal duel but Ruby, with her supernatural powers and immortality quickly gains the advantage against her all-too-human opponent, ultimately overpowers Kelly and kills her in a most ironic fashion: with the Kandarian dagger, a weapon that was meant to kill deadites and demons. Now standing tall as the victor, Ruby gets another urgent contact from Kaya using Necronomicon saying that The rift is even further weakened, and Ruby claims that she has just found a vessel body for Kaya: Kelly's corpse. Ruby then uses Necronomicon passages to free Kaya's soul from her millennial imprisonment and have the treacherous necromancer's soul occupying Kelly's body. Ruby then instructs Kaya/Kelly to infiltrate into Ash's team and drive a wedge between Ash and his daughter Brandy in her ultimate attempt to destroy the Prophesied One and his living offspring.

Ruby's demon child has fully matured into Ash lookalike. Seeing that his demonic arm sticks out like a sore thumb, Ruby instructs him to sever that demonic saw arm of his and replace with chain saw identical to that of real Ash's saw arm, to which the spawn complies.

Anticipating Brandy's coming to the prom, Ruby instructs her Ash-spawn to infiltrate into the high school and slaughter as many students as he can before real Ash shows up, effectively framing the real Ash and kill him in order to take his power and make her child as the new Prophesied One. The real Ash, with the possession of Kandarian dagger eagerly goes to Brandy's high school to kill Ruby for good. Once Brandy and Ash's team arrives in prom party, Ruby, as usual, attempts to manipulate and confuse Brandy by claiming that not only her father is really a psychotic serial killer but also an evil entity. Ruby tells Brandy that she has been hiding things from her, that there is evil in Elk Grove, but that it’s all because of her father. Having a hard time believing, Brandy storms off. When they are alone together, Kelly, speaking as Kaya, voices her uncertainty of Brandy's newfound bond with her father can be broken. But Ruby tells Kaya to keep prodding Brandy while her demon spawn would carry out the rest of her scheme. Ash-spawn, initially picking off few students who are isolated from the dance party, meets Brandy and shows her his demonic facade, causing her to become frightened and running back to the dance hall where Ruby is. Soon Ash-spawn crashes into the main dance hall, massacring teens left and right, turning the party into a sea of blood. Then Ash-spawn quietly slips off just before real Ash arrives at the scene of carnage.

Ruby’s reason behind engineering of this massacre is to have doppelganger Ash show up at the high school dance and start murdering people, showing himself to be an evil demon to Brandy, and then hide away when the real Ash comes by to save Brandy so she will be thoroughly convinced that her father is really evil and he needs to be stopped.

After Ash-spawn left and real Ash came in, Ruby uses her power to seal off exits, trapping all remaining survivors inside the dance hall. Ruby, in an attempt to break Brandy's bond with her father and to have her kill him, plunges herself upon Ash's chainsaw, faking her death, trying even more to convince Brandy that her father is evil and giving the impression that she died trying to protect Brandy. Fortunately however, in spite of all chaos and confusion going on in her head Brandy cannot bring herself to kill Ash. Pablo, who arrives at the high school to warn Ash of Kelly's death and someone else is occupying Kelly's body, encounters and exposes Ash-spawn. The two then engage in a fight that lead them barging back into the dance hall, revealing the demonic doppelganger before real Ash, confusing everyone present including Brandy. After being cornered Ash-spawn was finally silenced by real Ash with two boomstick shots to the head. Ruby's conspiracy of making her Ash-spawn as the new chosen one had failed.

Before Pablo can tell Ash the fate of real Kelly, Ruby becomes infuriated of being constantly thwarted and her grand machination ruined by Ash. The Demon Woman of Fire rises up to her feet much to the astonishment of all survivors present. Ruby cracks in fury and throws Kandarian dagger at Ash/the Prophesied One but Brandy, who by now realizes her father had been right all along, shields her father, takes the dagger in her back instead and dies. Taking advantage of Ash who is distraught over the loss of Brandy, Ruby escapes.

To be continued...