Almost two decades after it first aired, Supernatural remains one of the longest-running live-action fantasy series in the United States. Soon after its conclusion in 2021, it was announced that a spinoff prequel series called The Winchesters is in the works and fans can only hope that it will be as good as its predecessor.

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Supernatural was continually bringing something new to the world's television screens as the unique storylines never failed to keep fans wanting more. The series had its highs and lows, but each season has one episode that stands out by reflecting its originality and getting the best rating on IMDb as a result.

Season 1: "Devil's Trap" (9.3)

Dean and Sam with their father at a hospital in Supernatural

With everything that happens in the following 14 seasons, it's easy to forget that Supernatural started as a story about two brothers searching for their missing father. But what no one can forget about is the major cliffhanger of the first season's finale.

Sam rushes his family to the hospital when a truck suddenly crashes into their car in what looks like a fatal car crash. The season ends with the three of them unconscious and bloody and the viewers are left wondering about the fate of their favorite characters. It was certainly something that had fans on the edge of their seats for months since many shows weren't afraid to kill off major characters. Whether this would follow suit was only something time would tell.

Season 2: "All Hell Breaks Loose: Part 2" (9.5)

Dean hugging Sam and crying in Supernatural

Azazel's scheme resulted in one of the most shocking deaths of Supernatural as Sam was fatally injured at the end of the previous episode.

Dean makes a crossroad deal with a demon to bring Sam back to life in exchange for his soul. Sam's resurrection was one of many but in the second season's finale, it was certainly the most unexpected.

Season 3: "Mystery Spot" (9.5)

Sam holds a dying Dean in his arms

The third season was much shorter than the rest, but even with only sixteen episodes, it still managed to bring amazing episodes and keep things interesting.

However, one that stood out the most was "Mystery Spot," in which Sam gets stuck on a time loop, reliving the same day over and over again. Each day would end with Dean dying in unexpected ways, and the next would begin with Sam waking up to Asia's "Heat of the Moment" (which was undeniably one of the best songs featured on Supernatural). Compared to the other episodes in the series, this was quite light-hearted and humorous, which made it a memorable watch.

Season 4: "Lazarus Rising" (9.4)

Castiel with his wings spread in Supernatural

Supernatural is known for bringing its two main characters back from the dead time and time again and the fourth season premiere featured one of the most shocking resurrections. After he was dragged to Hell at the end of season 3, Dean is mysteriously brought back to life and has to crawl out of his own grave.

Moreover, "Lazarus Rising" introduces Misha Collins' character, Castiel, the angel who raised Dean out of hell and quickly became a fan favorite.

Season 5: "Swan Song" (9.7)

Dean and Sam looking down at a hole on Earth in Supernatural

The fifth season finale marks the end of the main storyline and the departure of Eric Kripke as showrunner. As the apocalypse approaches, it was up to the "Team Free Will" to save the world.

Supernatural never failed to close a season with a mind-blowing finale and "Swan Song" is the most iconic example of that. After Sam agreed to be Lucifer's vessel, all hope seemed lost. Fans watch at the edge of their seats as Dean goes against the Devil himself.

Season 6: "The French Mistake" (9.6)

Dean and Sam looking confused in Supernatural

In the most meta episode, Sam and Dean are transported to a different dimension where their lives are played out as fiction in a TV show called Supernatural. The two of them are Jared Padalecki and Jensen Ackles (who are actors that play the roles of Sam and Dean).

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"The French Mistake" is named as one of the best episodes of the show as its light-hearted, self-ridicule and the popular inside jokes make for a hilarious watch.

Season 7: "Death's Door" (9.2)

Two men standing next to each other in Supernatural

One of the most heartbreaking Supernatural episodes, "Death's Door" saw the death of Bobby Singer, who died as a result of a gunshot wound from the previous episode.

Sam, Dean, and fans alike spend the entire episode waiting for Bobby to finally recover but they are all left heartbroken as he finally takes his last breath. Bobby was the only character other than the Winchester brothers, that has been in the show from the very beginning, and his death was completely unexpected.

Season 8: "Sacrifice" (9.3)

Sam looking emotional in Supernatural

In "Sacrifice," the Winchesters were attempting to complete three demon trials that would close the Gates of Hell. But, as Dean tries to warn Sam that completing the third trial would kill him, Sam reveals that he was okay with dying as he felt that he had to atone for letting his brother down in the past.

This episode was packed with tear-jerking scenes and amazing visuals, while Jared Padalecki and Jensen Ackles gave an impeccable performance, perfectly demonstrating the brotherly chemistry between them.

Season 9: "Do You Believe In Miracles?" (9.3)

Dean with black eyes in Supernatural

"Do you believe in Miracles?" gives a shocking end to the ninth season. It's not often that a Winchester death looks permanent but after a whole season of watching Dean struggle with the Mark of Cain, fans feared the worst when death finally caught up to him.

But that was only until the very last second of the season finale when a presumably dead Dean, opens his eyes, revealing his new black demon eyes. Fans were left stunned and eagerly anticipating the next season.

Season 10: "Fan Fiction" (9.5)

Dean addresses the cast of the Supernatural musical

"Fan Fiction" was Supernatural's 200th episode and it was essentially a love letter to the series and a show of appreciation to the fans. The brothers find themselves investigating a case at a school that's about to put out a musical based on Chuck's books about the Winchesters' lives.

The episode is hilariously meta, full of subtext and features some unforgettable music numbers (like "Single Man Song" and their own cover of "Carry On My Wayward Son").

Season 11: "Baby" (9.5)

Dean inside a car leaning back in Supernatural

Anyone who watched Supernatural knows that characters come and go all the time. But the one character who has remained by the Winchesters this whole time is Dean's 1967 Chevrolet Impala, or as he likes to call it, Baby.

RELATED: Supernatural: Dean's 10 Best Quotes About 'Baby'

"Baby" is rightfully the best-rated episode of the show as it displays a very unique form of storytelling. It follows Sam and Dean on a regular monster hunt but all of the events of the episode are seen from the car's perspective.

Season 12: "Stuck In The Middle (With You)" (9.0)

Characters from Supernatural sitting in a table otgether

This episode stands out for its unique style as it resembles several Quentin Tarantino movies. Sam, Dean, Castiel, and Mary, develop a plan to lay an ambush on a Prince of Hell.

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During the fight, Castiel was seriously injured, but as an angel, his resurrection would be near-impossible which made his goodbye to the Winchesters a real tear-jerker. This episode was full of suspense as fans feared for Castiel's fate.

Season 13: "ScoobyNatural" (9.6)

Sam, Dean, and Scooby-Doo in Scoobynatural

After 13 seasons, viewers would think that Supernatural has done everything there is to do, yet it still managed to find creative ways to keep fans interested. In this wildly unique episode, Sam, Dean, and Castiel are sucked into an episode of Scooby-Doo

In order to find their way back, they have to finish a ghost hunt together and interactions between the Supernatural trio and the Scooby-Doo gang are iconic. "ScoobyNatural" is the only animated episode of the show and the most unexpected crossover.

Season 14: "Lebanon" (9.3)

Mary and John Winchester are reunited in Lebanon in Supernatural

Supernatural's 300th episode brought waves of nostalgia along with the return of John Winchester.  Thanks to a mystical pearl, Dean accidentally summons John from 2003 and for a while, the Winchester family is reunited again. However, John's return altered the timeline, leaving the brothers in difficult predicaments.

Even though their reunion couldn't last because of the implications it had on the timeline, it provided some much-needed closure for the characters and gave them the opportunity to say goodbye.

Season 15: "Last Holiday" (8.7)

Mrs. Butters and Dean in Supernatural

Some fans felt like the last season of Supernatural didn't manage to live up to the expectations. However, "Last Holiday" quickly became a fan favorite for its wholesome scenes. In the episode, they accidentally released a wood nymph named Mrs. Butters, who used to live with the Men of Letters and she brings an optimistic atmosphere to the Bunker.

In all fifteen seasons, the characters were rarely given any breaks, so it was refreshing to see the Winchester family take time between hunts to relax and celebrate holidays together.

NEXT: Everything We Know About The Prequel "The Winchesters"