Summary

• Key episodes like the 'Pilot' & 'Devil's Trap' set the tone and narrative foundation of Supernatural.
• Introduction of pivotal characters like Castiel and Chuck change the series dynamics and pave the way for future storylines.
• Finales like 'Sacrifice', 'Alpha and Omega', 'Carry On' deliver powerful conclusions that define the essence of Supernatural.

Supernatural had 327 episodes by the time it wrapped its fifteenth season, with some exceptional episodes that defined the show. Supernatural began airing in 2005, and quickly built a dedicated fanbase. The series continued to be popular throughout its entire run, only coming to a halt in 2020 after fifteen seasons when the cast and crew decided to lay the show to rest.

However, in that time, Sam and Dean Winchester firmly established themselves as one of the most entertaining duos on TV. The series experienced plenty of changes throughout its lengthy run, but some episodes were pivotal to the overall narrative, while others served up equally fun monster of the week stories. While both were great, the episodes that changed the game are unmissable.

12 "Pilot"

Supernatural Season 1, Episode 1

Obviously, the first and most important episode to come out of the series is the "Pilot." The first episode perfectly sets up the events of the show, introducing the relationship between the brothers, and their willingness to put aside their differences and go take care of business. The show establishes its themes, tone, and all of the most important elements right at the top, setting up the series to be a huge hit.

The chemistry between Sam (Jared Padalecki) and Dean (Jensen Ackles) makes this episode, and indeed, the show what it is, and it's apparent from the start. While both brothers want different things out of life, they are willing to move mountains to support each other and chase a common goal. The episode also features plenty of frightening moments and twists that help establish the series.

11 "Devil's Trap"

Supernatural Season 1, Episode 22

One of the best elements of the entire show is the outstanding finales and the cliffhangers between seasons. After Supernatural season 1 sees the boys embark on a hunt to track down their missing dad, the season 1 finale has them getting closer than ever. However, all is not as it seems, and the show ensures that viewers don't get too comfortable with their expectations before subverting the story.

This episode also introduces a key player in the Winchester team, their unofficial uncle, Bobby. Bobby is always at hand to offer advice when the boys' father is not in the picture, he is also very stern, and has a soft spot for the boys. The boys face off against the demon who killed their mother and Sam's girlfriend. However, when he possesses their father, things get messy. The episode then concludes with another twist and cliffhanger, setting expectations for how the rest of the series will go on.

10 "All Hell Breaks Loose" Part 1 & 2

Supernatural Season 2, Episodes 21 + 22

It may be cheating, but considering season 2 had a rare two-part ending, it's worth including Part 1 and Part 2 as a single story. The boys came face to face with Azazel, the yellow-eyed demon once again, but this time, he came prepared with some champions of his own. Throughout the season, Sam has been distant with his brother as he learns about the demon blood in his system and the powers that they afford him. However, when pitted against other initiates, Sam is caught off guard and killed.

Part 2 then builds on this narrative with Dean making a deal to trade his life for Sam's, a single year before the debt is to be collected. This is the first of many times throughout the show that the boys make back-door deals to stay out of the afterlife, which makes it one of the most important of the show. This episode also concludes the narrative with Azazel and John Winchester, allowing the series to move into a new stage of life.

9 "Lazarus Rising"

Supernatural Season 4, Episode 1