On this week's episode of Supernatural…
Four years ago, Sam and Dean, with the help of Nora, exorcised a demon from a man named Jeffery.
Back in present time, the brothers come across killings that are similar to the ones made by the demon.
They come across Jeffrey and with the help of Nora attempt to find the demon.
Unfortunately, Sam's hallucinations of Lucifer get worse and he uses Lucifer's help to learn the truth. The demon hasn't returned, but Jeffrey wants it to.
Nora's son had been kidnapped and she was forced to help Jeffrey summon the demon back. It returns, but Nora exorcises it back to hell. Dean shoots Jeffrey.
With the case closed, Sam tries to use his tricks to get rid of Lucifer, but he has managed to worm his way further into his brain. Sam begins hallucinating hellfire.