A bone-chilling theme song "O Death" accompanies the preview of next week's "Supernatural" episode. Dean has a meeting with Death (guest star Julian Richings) to discuss Lucifer, and an unholy alliance is formed at a very high price for Dean. And this kind of expensive deal has nothing to do with money.
Crowley (guest star Mark Sheppard) tells Bobby he will give him the location of Death, the fourth horseman, in exchange for his soul. Knowing Sam and Dean need that fourth ring to stop the Apocalypse, Bobby reluctantly agrees.
Meanwhile, Sam and Dean confront Pestilence (guest star Matt Frewer), but he unleashes a deadly virus upon them, so Castiel must intervene on their behalf.
"Two Minutes to Midnight" airs on May 6 and the episode after that would be the season finale.