Supernatural Season 5 Episode 19: Hammer of the Gods

Sam and Dean are kidnapped by a group of gods, including Kali, Ganesh and Baldur and held hostage in a small hotel. The gods want to use Sam and Dean as bargaining chips to stop the Apocalypse, but Gabriel shows up and warns them that if Lucifer finds them he will kill them all. Unfortunately, one of the gods turns on the rest and Lucifer appears

Supernatural Season 4 Episode 19: Jump the Shark

Sam and Dean are contacted by one Adam Milligan who claims to be John Winchester's son. The boys immediately suspect a demon trap and go to investigate. Adam turns out to legitimately be John's son and Dean is furious that John kept Adam's existence from them as well as sheltered Adam from the hunting life. Meanwhile other supernatural forces are at work, which lead to a tragic twist that neither Sam, Dean, or their new sibling could have guessed.

Supernatural Season 2 Episode 19: Folsom Prison Blues

When an old block is reopened in the Green River County Detention Center after thirty years, a fiend is released, killing the interns. Three months later, Dean and Sam are arrested during a heist to be sent to the haunted prison to help Deacon, a former friend of their father. While FBI Agent Victor Henricksen presses Dean, the public defender Mara Daniels believes the brothers are not guilty of most of the inconsistent charges against them, and helps the Winchester brothers in the end.

Supernatural Season 1 Episode 19: Provenance

A young couple is murdered in their home shortly after buying an antique painting of a family portrait circa 1910. Upon reviewing the painting's provenance, Sam and Dean learn that everyone who has ever bought the painting has been murdered and race to discover how the portrait is causing the deaths before it can claim its next victim.