As Supernatural viewers gear up for the events of "Keep Calm and Carry On," talk of the series' future has fans biting their nails. With nearly 250 episodes under their belts, Jared Padalecki and Jensen Ackles recently addressed the words all fans dread - the series finale.

Supernatural's 12th season will begin this October on The CW, making the monster-slaying drama the longest running sci-fi show in the nation. The Winchester brothers have crisscrossed the country since 2005, traveling from heaven to hell and back again. Sam and Dean can't hunt the paranormal forever, however, nor would we expect Padalecki and Ackles to want to.

At the moment, the actors are shooting for 300 episodes, which would take the series into season 14. Should Supernatural make it onto the 2018-2019 schedule, the Texas natives will consider laying down arms.

"If we don't make it to 300, I think Ackles and I will both be truly bummed," Padalecki told Entertainment Weekly. "When we get to 300, I think Ackles and I will think it might be time to say bye. There's a chance that changes, but we certainly do not take it for granted that we're going to make it to 300."

Padalecki and Ackles have debated the nature of a Supernatural finale in the past, both championing the ideas that the heroes should either go out Bonnie and Clyde style or in a fade-to-black moment as they head off to battle a seemingly insurmountable enemy, fates unknown. Should execs choose the latter option, Ackles certainly isn't adverse to the idea of a follow-up film.

"A feature film probably wouldn't be until the show stopped airing as a television series," Ackles told a packed house at Creation Entertainment's Chicago Salute to Supernatural earlier this month. "When - if - that day does come."

For now, kick back, relax, and tune in for season 12 starting Oct. 13 on The CW. Or, in other words, "Keep Calm and Carry On" (see a preview below).

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