- "I say we cap 'em both."
- ―Emilio to Krazy-8 about Walt and Jesse.
According to Jesse, they met when they were still in elementary school.
Jesse mentions that Saul Goodman provided Emilio legal representation on at least two occasions, getting him acquitted both times despite much evidence against him ("").
Emilio is arrested during a raid on a house in which the DEA is looking for meth supplier who goes by the street name "Captain Cook". Emilio makes bail and mistakenly suspects that his partner, Jesse Pinkman, ratted him out to the police. He forces Jesse to lead him and Krazy-8 to his new partner, Walter White, in Emilio's 1980 Buick Regal. Emilio recognizes Walt from the time of his arrest and suggests killing both Walt and Jesse. Walt convinces them to spare their lives if he teaches them his meth formula.
While the three are in the the RV in the desert, Walt deliberately causes a chemical explosion and flees, trapping Emilio and Krazy 8 inside the RV with deadly phosphine gas and leading to Emilio's death ("").
Emilio's corpse is subsequently disposed of by being dissolved in hydrofluoric acid in Jesse's bathtub (""). However, the corrosive acid eats through the bathtub and the floor, splattering Emilio's bloody, liquefied remains on the floor. Walt and Jesse later clean up the mess ("").
- Emilio was the first character to die in Breaking Bad.
- Emilio was Walter White's first kill.
- Emilio shares the same surname as the character that portrays him