"Supernatural" season 15 episode 20 marks the end of an era. After a decade of hunting demons, the journey of Sam and Dean Winchester is speculated to finally come to an end with an epic battle with god in the series finale. Here are a few spoilers about how it all comes to an end.

[Spoiler alert! This article contains spoilers for "Supernatural" season 15 finale.]

Fans would agree that the past few episodes have been heartbreaking with fan-favourite Castiel sacrificing his life to save Dean, who he confesses he has loved all his life. While Sam and Dean are devastated, Chuck/God continues to unleash his havoc.

"Supernatural" season 15 episode 20 is titled "Carry On" and it will bring an end to the rampage created by Chuck. It is an episode heavy-on-emotion whereby the Winchester brothers take the final journey in their demon-hunter career to save people. Meanwhile, The CW is keeping things under the wrap and refrains from giving out specific details about the finale.

"THE END – After 15 seasons, the longest running sci fi series in the US is coming to an end. Baby, it's the final ride for saving people and hunting things," reads the official synopsis for episode 20 by the network as posted on Spoiler TV.

Nevertheless, the showrunner Andrew Dabb has let out some important information about how the series will conclude for Jared Padelecki and Jensen Ackles' characters. Speaking with TV Line, Dabb revealed that the brothers will not end up separated. They will be as they were in the beginning.

"Sam and Dean started this journey together, and they are ending this journey together," Dabb said.

So, fans can expect some emotional moments but it is not going all that sad by the end of it.

"Do they end it in the same place? Do they end it in the same way? Are they both on the same page when it ends? That remains to be seen in the last episode. But the show started about these two guys, and it ends about these two guys," Dabb added.

The finale is directed by Robert Singer and written by Dabb.

In addition, the "Supernatural" series finale will air a celebratory episode featuring interviews of all the prominent stars of the show including Padalecki, Ackles, Misha Collins, and more. It will air an hour before the final episode of the series.

"Supernatural" season 15 episode 20 airs Nov. 19 at 9:00 pm ET on The CW.

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Supernatural stars Misha Collins, Jensen Ackles and Jared Padalecki The CW