The influence of cannot be overstated. It paved the way for serialized genre shows like The Vampire Diaries (which copied the "five-season mythology" arc), Grimm , and Teen Wolf . It proved that a "bottle episode" about a ghost in a 1950s whorehouse could lead to the literal end of the world.
The road ends at Season 5. Everything after that is just a bonus. Supernatural Seasons 1-5
The Season 5 finale, titled "Swan Song," was intended to be the series finale and is frequently cited as one of the greatest episodes in television history. Aesthetic: The influence of cannot be overstated
The Premise: "Saving People, Hunting Things, The Family Business" titled "Swan Song