Now approaching the end of its ninth season, US sci-fi/fantasy show Supernatural is making its way up the list as one of the longest-running TV dramas of all time, with more than 190 episodes having aired since 2005.
What started off as a show about two brothers who fight monsters has developed over time into an epic action-packed tale of angels, demons and monsters - and so far it shows no signs of stopping.
Having gone from strength to strength in almost a decade, Supernatural has attracted an astoundingly large and dedicated fan base, forming an internet community of millions all over the world.
Several Supernatural conventions take place every year - from Rome to Melbourne- without fail, with fans coming in their thousands to celebrate the show together.
But what is the secret to the long life of this show? And why does it attract the most dedicated of fans, willing to travel miles for the sake of discussing a TV series?
It’s typical sci-fi/fantasy escapism
Watching the long-suffering Winchester brothers come up against monsters, demons, angels and one apocalypse after another is a sure-fire way to make your own troubles seem small.
Not only does this draw fans in early on, but it keeps them watching- over the years they've become so invested that they'll keep watching until the bitter end.
But it’s also about the real world
It’s the strange, turbulent, yet unconditionally loving family relationships that drive the over-arching Supernatural storyline.
Sam and Dean struggle with their sibling relationship throughout the show, while their angel friend Castiel deals with divides within his own family (we all know what happened with Lucifer), and finds himself having to choose between his family in heaven and his love for humanity.
And it makes you cry
A combination of heartfelt writing and beautiful acting means that Supernatural isn't just a fantasy show, it’s also a drama guaranteed to make you sob into a pillow at some point.
Sam Winchester's demon blood problem will strike a chord with anyone who’s dealt with addiction, and Castiel's conflicted search for approval from his family (who just happen to be the heavenly host) is something anyone with family troubles can relate to.
But it's also hilarious
The show is filled with snappy and hilarious one-liners, the majority of which come from lovable villain Crowley, who gives just the right amount of comic relief to a show that might otherwise be too depressing.
There are also intermittent episodes throughout that leave behind the apocalypse temporarily and find Sam and Dean engaging in funnier antics, including an episode where Sam and Dean accidentally become the actors that play them, and another where the characters inadvertently turn up at a Supernatural convention.
Plus there's an undeniable homoerotic subtext
'Shipping', originally formed from the word 'relationship', has recently come to the attention of mainstream media, but fans have been willing characters to get together for decades.
If fan conventions are anything to go by, one of the things that keeps fans watching is the (frankly undeniable) homoerotic subtext that runs throughout the show, most prominently between Dean Winchester and the angel Castiel.
'Destiel' most likely started as a fandom quirk, and a joke among the writers. Over time, though, cast and producers of the show have acknowledged repeatedly that there is an ambiguity surrounding the nature of their relationship. Producers know the show owes some of its success to this phenomenon and will play up to it as much as they can.
Fans can’t stop talking about it on the internet…
It's a running joke on Tumblr that everyone always knows what is happening on Supernatural, even if they have never watched it.
The internet community means that even when a Supernatural season ends, people continue to talk about it. If there are gaps in the show, the fans will fill them with their own creativity – writing stories, making art and speculating about what will happen in the future.
…which means the fans are in control
One of the most notable things about the 'shipping' phenomenon is that it shows, to an extent, that the fans are as much in control of the show as the producers.
In recent years, fans have taken control of what they watch thanks to the internet. Writers now know exactly what their fans want to see, and while they don't always give it to them, it's almost always taken into consideration.
And the actors reward the ‘Supernatural Family’ fanbase
Supernatural has the power to last longer than other shows because it has become more than a show, it's a community.
This community, which the actors call the 'Supernatural Family' creates a tight-knit bond between fans, cast and crew, which means fans are willing to stick with the show no matter what.
Misha Collins has been to fifty seven fan conventions, despite only having been in the show since season four (Jared Padalecki, who plays Sam Winchester, comes in at a close second, with fifty four).
The Supernatural season nine finale airs in the US tonight on The CW.