I watched the Supernatural Season 10 finale tonight. When it finished, I felt like I should go back and watch the Season 5 finale to get something more satisfying.

Supernatural is something of a guilty pleasure of mine. I first caught an episode while home sick from work one day – the Season 3 episode “Jus in Bello”. It intrigued me at the time, but I never got around to watching more of it (in part because, at the time, I didn’t have Netflix).

Fast forward to two years ago, when I began watching Supernatural on Netflix to catch up, and then getting one episode per week like longtime viewers. Ultimately, after watching the Season 10 finale, I concluded the show’s run could be a modern case study in what happens when the story goes too long.

The ur example, I suppose, would be Sherlock Holmes – Doyle wound up writing Sherlock stories much longer than he ever intended, bringing him back after killing him in “The Final Problem.” But Supernatural is a great modern example.

For those uninitiated in the ten-year-old show (which was renewed for an 11th season), it follows the exploits of two brothers as they battle supernatural evil in various forms. Elder brother Dean followed his father’s footsteps as the loyal son, while younger brother Sam rebelled and abandoned the lifestyle of the “hunter”, only to be pulled back in by Dean during a quest to find their missing father.

The series started as a “monster of the week” type show, with a surprisingly creepy atmosphere and genuinely threatening creatures, overlaid with rock music and a cool classic car. By the end of Season 1, though, the show had become something more – Jensen Ackles and and Jared Padalecki found a surprisingly convincing chemistry as brothers who loved and hated each other all at the same time.

Season 1 ended with a gut-wrenching twist; after escaping the Yellow-Eyed Demon, the murderer of their mother, with their father in tow, their car was t-boned intentionally by a demon-possessed semi driver, leaving open the question of who had survived and who had died.

The following season would end with revenge upon the Yellow-Eyed Demon for the death of both the boys’ parents, but the unleashing of hundreds of demons on Earth, setting in play the story elements that would wind through the next three seasons, culminating with Season 5’s season-long story arc of the boys’ campaign to kill the devil to prevent literal Armageddon. Ultimately, they prevailed, but with younger brother Sam sacrificing himself to bind the devil again.

The first five seasons followed a great story arc. The brothers grew in both skill and maturity, starting as young hunters inexperienced enough to be troubled by simple hauntings to veterans capable of taking the war to the devil. As brothers, they began as immature siblings with trust issues and tension over their father’s love but blind loyalty to each other, repeatedly lying to each other but eventually growing to trust each other, with Dean willing to let Sam go at the end of Season 5 for the sake of victory.

While the story felt stitched together at times, their was also clearly a long story planned from the beginning, and the writers team executed their part with great pains. It doesn’t mean there weren’t flop episodes in there (Season 1’s “Bugs” immediately jumps to mind, or Season 3’s “Seven Deadly Sins”), but as an arc of episodic episodes it was amazing.

The problems began with Season 6.

In part, the story suffered from the “Nuke the fridge” problem. The Winchesters had beaten Lucifer himself; what could be more threatening than the Prince of Darkness himself? To continue the story, the writers had to undo far too much of what had happened in the first five seasons. Sam was resurrected after his heroic sacrifice, the brothers’ relationship backslid, and they seemed to have forgotten important lessons about hunting and brotherhood that they had spent the previous five years learning the hard way.

The big story arc involved a civil war in heaven after the derailing of Armageddon, but because it was beyond the boys’ capacity to help, it was largely executed off-screen, leaving the episodes feeling disjointed and unimportant. Not until the very end of the season did it seem to actually matter, and then it was quickly resolved.

Season 7 tried to bring back a “big bad” to defeat (which they did in the finale), and Season 8 wandered aimlessly for quite a while until they stumbled onto an epic quest to close the gates of Hell. Season 9 reverted to “brother lies to brother” for dramatic tension – after eight years of hunting together, you’d think they’d have learned to tell each other the truth, as those lies always backfire – and Season 10’s arc was about Dean under a curse.

Season 11 looks to be bringing in another “big bad” for them to fight – one that, by all rights – should be beyond their capability, since apparently it took God and the archangels to beat back the last time. (Side note – Season 11 could actually be a great throwback to Season 5 if the writers bring back the prophet Chuck and the two surviving archangels from their prison, but I’m doubtful about whether they’re willing to go that direction.)

Looking at the series as a whole, Season 5’s finale would have wrapped the series up in a neat bow. The ending wasn’t happy for all the main characters, but that’s okay. It was satisfying. Unfortunately, the money and the ratings were apparently more than satisfying, too, since they continued a story that clearly was finished.

None of this is to say that the later seasons didn’t have some good stories. For that matter, there are some standout episodes (including my favorite episode in the entire series, “Weekend at Bobby’s”, which was early in Season 6). As a whole, though, the arc storytelling simply lost its punch.

I’m a writer by trade – I’ve finished five novels (the first three were fanfictions that gave me the experience and the confidence to actually try something original), and I’m by no means an expert. I’m still honing my craft, and I suspect I will be for many years to come…probably until they plant a headstone on me.

But at some point, the story needs to end. When the good guys have won, and sacrificed, and learned their lessons, they need to be able to go home. Continually pitching them into the flames again and again ebbs the life and spirit of a work.

Let it go when it needs to go. Zombies are never a good thing. Dean himself states, “What’s dead should stay dead.”

So bring on Star Wars: The Force Awakens!