"El Brujo" was a shaman, and uncle to Pablo, who agreed to help Ash stop the evil that has been unleashed on the world again.
Pablo takes Ash to meet his shaman uncle, a "Brujo", who may be able to help. Along the way, Kelly gets sick and acts strangely, having been unknowingly possessed by the demon Eligos. Eventually the Brujo gives Ash a drug-induced vision of himself relaxing on a pier in Jacksonville, Florida (Ash's idealized vacation spot), where his pet lizard Eli appears and tells him he must bury the Necronomicon deep in the place where everything started – the cabin in the woods. During the trip, a possessed Kelly attacks Ash.
The Eligos-possessed Kelly convinces Pablo and his uncle that Ash is the one possessed. The Brujo prepares for an exorcism while, back in Ash's trailer, Kelly tries to seduce Pablo and later kill him. Once the demon reveals himself the Brujo performs the exorcism on Kelly, forcing Eligos to leave, but not before the Brujo is killed. During a funeral for the Brujo, Pablo takes his uncle's sacred medallion. Back at the trailer, Pablo gives Ash a new mechanical hand that he had been working on.
Later, Ruby and Amanda arrive at the Brujo's ranch just having missed Ash, but the charred (and now possessed) skeleton of the Brujo emerges from the funeral pyre and confronts Ruby telling her that she will never have the book for herself. The two fall into the pyre which then explodes.
When Pablo becomes possessed by the Kandarian Demon in the season three episode Baby Proof, he finds himself in a realm between life and death, where he meets the Brujo, who explains that Pablo must now perform a ritual to return to life and succeed him. He successfully completes the ritual and comes back to life.