The paranormal procedural Supernatural follows the Winchester Brothers, Sam (Jared Padalecki) and Dean (Jensen Ackles), as they drive around America fighting monsters. While each of the show’s fifteen seasons has its own major throughline, the bulk of its three hundred and twenty-seven episodes center on isolated incidents between the hunters and some monster-of-the-week. These one-off adventures are sometimes derogatorily referred to as “filler” episodes, but they make up the backbone of the series.

Supernatural delivers some emotionally devastating, jaw-dropping, and earth-shaking milestone episodes, and it is only able to do that because of the work done in these filler episodes. Episodes that don’t directly relate to a season arc add depth to character arcs and establish lore that a series relies on. Plus, they hold the audience’s attention, while building a crucial emotional bond between the viewers and the heroes.

10
Dean is Framed for Murder
Season 1, Episode 6: “Skin”

The Season 1 episode “Skin” is a flawless stand-alone episode, that sees the brothers hunting a shapeshifter. Unfortunately for them, the shifter realizes they’re on its tail and turns into a duplicate of Dean. The brothers are able to defeat the cunning monster, but not before it implicates Dean in a killing spree.

Dean’s status as a wanted fugitive never becomes the primary focus of a season arc, but it causes plenty of problems for the boys in the coming years. It forces them to be on high alert around authorities and robs them of the option of ever fostering relationships with national law enforcement. In fact, this episode directly leads to the introduction of a recurring antagonist, FBI agent Victor Henriksen (Charles Malik Whitfield).

9
The Show Introduces the Concept of “Good” Monsters
Season 2, Episode 3: “Bloodlust”

While investigating a series of mysterious decapitations, Dean and Sam cross paths with another monster hunter by the name of Gordon (Sterling K. Brown). Gordon explains that he’s found a vampire nest, and he and Dean bond over the thrill of hunting. Meanwhile, Sam discovers the vampires are pacifists, subsisting solely on cow blood. Gordon maintains all vampires are evil and seeks to kill them regardless, leading the brothers to protect the vampires from their former ally.

Until this point in the narrative, all monsters had been portrayed as mindless creatures intent on harming humans. This episode challenges that and causes Dean to fearfully reflect on the possibility he’s harmed innocents. While the series can be notoriously inconsistent with character arcs, this has a lasting impact. It prevents every episode from becoming pure shoot ’em up and lays the precedent for several friendly, inhuman characters in the show’s later seasons.

8
The Winchesters Learn about Demonic Pacts
Season 2, Episode 8: “Crossroad Blues”Dean talks to a woman by a car at night in Supernatural.

After a series of mysterious deaths and reports of a ghostly dog, Sam and Dean connect the victims to the same bar. Digging deeper, they uncover the establishment was by a crossroad, and stumble upon lore that reveals that crossroads demons regularly make deals for human souls. The Winchesters successfully trap the demon behind this slate of deaths and force her to release her final victim from his contract.

This episode plays as an isolated incident, but it’s actually a Checkov’s gun. When Sam dies at the end of Season 2, Dean relies on his newfound knowledge of crossroad demons to resurrect him. This idea of demonic bargains runs through the series and the brothers even begrudgingly form a working relationship with the King of Hell, a crossroads demon named Crowley (Mark Sheppard).

7
Dean and Sam Debate the Existence of Angels
Season 2, Episode 13: “Houses of the Holy”

Under the instruction of an “angel,” everyday citizens begin murdering their less scrupulous neighbors. With Sam inclined to believe a real angel may be responsible for the vigilante justice, the case sparks a discussion between Sam and Dean. Sam is shocked to learn Dean fully discounts the possibility that angels could exist, noting they’ve encountered countless mythical creatures. Dean argues that with all the evil he’s seen in his life, he can’t believe there’s any force of good out there. The culprit in this particular case turns out to be the ghost of a confused and vengeful priest.

Two seasons after this episode, Dean and Sam find themselves at the center of the war between heaven and hell. Beyond that, they learn they’re destined to be the Earthly vessels for the archangels Michael and Lucifer, respectively. This revelation casts this episode in a whole new light. What once felt like an intimate character story, becomes the emotional underpinning of a major future story arc. Dean’s anger at his destiny and struggle to believe he’s worthy of angelic attention are rooted in this Season 2 one-off.

6
Tall Tales Forever Changed The Show’s Tone
Season 2, Episode 15: “Tall Tales”

The Season 2 episode “Tall Tales,” takes an unconventional approach to storytelling. Sam and Dean recount the troubles they’ve been having during a recent investigation of their friend Bobby Singer (Jim Beaver). Depending on which brother is narrating, one of the Winchesters is always acting as a cartoonishly exaggerated version of themselves. The case itself centers around a college campus, where residents continually encounter impossible events. Bobby helps the brothers see they’re being toyed with by a trickster god and the trio slays the trickster — or so they think.

A wildly successful episode, “Tall Tales” also marks the first time Supernatural fully leans into camp and humor. The show had funny moments before, but nothing on the scale of a frat boy being forced to slow dance with a little gray man. This episode helped the series move away from being a rigid horror series and develop its own unique voice. Plus, it gifts the fans with a beloved villain. The ‘trickster’ behind the madness returns for several episodes and is even retconned into being an undercover archangel.

5
Ben and Lisa Take on Surprising Prominence
Season 3, Episode 2: “The Kids Are Alright”

Dean swings by an old girlfriend’s house and lands smack in the middle of a case. Hoping to have a quick fling with former one-night stand Lisa (Cindy Sampson) Dean discovers she has a child who bears striking similarities to him. While Ben (Nicholas Elia) turns out not to be Dean’s son, he is in danger as the neighborhood children are being kidnapped and replaced with changelings. The brothers defeat the monsters and rescue the kids. Dean rides off, reflecting on what his life could’ve been.

This encounter initially serves as a kind of quick ‘what if’ moment for Dean. However, his brief time with Ben and Lisa has a lasting impact. When he tries to quit hunting in Season 6, Dean winds up rekindling his romance with Lisa. Dean’s old life comes back to haunt him, and he’s forced to give up his hope of normalcy.

4
Dean and Sam Meet the Supernatural Fandom
Season 4, Episode 18: “The Monster at the End of the Book”

Sam and Dean are shocked to come across a book series called Supernatural, which accurately depicts the events of their lives. The search for their author leads them to Chuck Shurley (Rob Benedict), who regularly has visions of the Winchesters. The brothers grapple with the concept of predestination but ultimately are able to subvert Chuck’s prophecies and return to their normal lives.

This episode leaves lasting marks on the show in two major ways. Firstly, it introduces the concept of a Supernatural fandom within the story. This idea is expanded on in later episodes when the brothers stumble upon a fan convention, tangle with an obsessive fan girl, and encounter a school musical based on their lives. More importantly, the character of Chuck evolves quite a bit over time. Initially introduced as a prophet, he reappears in the narrative several seasons later as God himself, even becoming the show’s final big bad.

3
Issues Around Castiel’s Vessel Are Resolved
Season 4, Episode 20: “The Rapture”Supernatural

One of Winchester’s most stalwart allies is the angel Castiel (Misha Collins), who has possessed a man named Jimmy Novak. In “The Rapture”, Jimmy regains control of his body and returns home. Demons pursue Jimmy, threatening his life and that of his family. Using Jimmy’s daughter as a vessel, Castiel saves the family, but Jimmy is mortally wounded. Jimmy begs Castiel to use him as a vessel once he’s died, and the angel complies.

A ‘filler’ episode often shifts focus from the main character to flesh out a supporting character, and that’s precisely what “The Rapture” does. Because of Supernatural lore, Castiel can only exist in a human’s body, which leads to a number of moral complications. By killing off Jimmy and letting Castiel be his own independent entity, the story opens a million avenues for the character.

2
Sheriff Jody Mills Learns About the Paranormal
Season 5, Episode 15: “Dead Men Don’t Wear Plaid”

In Sioux Falls, South Dakota, the dead have begun to rise, including Bobby’s long-deceased wife. While the entire town is aware that these resurrections seem too good to be true, they can’t bring themselves to regret the return of their loved ones. One particularly poignant reunion is between local sheriff Jody Mills (Kim Rhodes) and her son. Eventually, the zombies go feral and all have to be put back into the ground.

While this episode is primarily about Bobby, Jody instantly wins over the hearts of the viewers and the writers alike. After learning about the existence of the undead, she becomes an amateur hunter herself. She frequently crosses paths with the boys throughout her adventures and is one of the leads of the show’s backdoor pilot episode, “Wayward Sisters.”

1
Nephilim Become Instant Power Players
Season 12, Episode 10: “Lily Sunder Has Some Regrets”

Castiel is disturbed when he realizes all the angels in his former garrison are being murdered, and looks into the death with the assistance of the Winchesters. They link the deaths to a woman named Lily Sunder. Castiel explains that a century ago, his garrison killed Lily’s child, a half-human half-angel being known as a Nephilim. Nephilim are supremely powerful, and their existence is forbidden by heaven. As the episode plays out, Castiel comes to realize the leader of his garrison manipulated him and his colleagues into murdering a human child out of a personal vendetta.

Not only is this the best Castiel-centric episode in the series, but it also sets up a vital foundation for the show’s final chapter. Much of the storyline in Supernatural’s final three seasons centers around Jack Kline (Alexander Calvert), a Nephilim the boys raise as a son. This isn’t the first episode to mention Nephilim, but it’s the first one to really dig into the concept. Given that Jack goes toe-to-toe with God in the show’s penultimate episode, it’s vital that audiences understand how strong Nephilim are in this universe. And this ‘filler’ episode makes that point loud and clear.

Source: cbr.com

By Ivaylo Angelov

Ivaylo Angelov born in Bulgaria, Varna graduated School Geo Milev is Tvserieswelove's Soaps Editor and oversees all of the section's news, features, spoilers and interviews.