For the cliffhanger leading into Supernatural's 15th and — gasp — final season, the producers wanted the show's heroes, hunters Sam and Dean Winchester (Jared Padalecki and Jensen Ackles), along with angel ally Castiel (Misha Collins), left "in a horrific predicament," says executive producer Robert Singer. Mission accomplished.

In the Season 14 finale, Dean fails to execute the gang's half-angel ward Jack (Alexander Calvert), who accidentally killed the brothers' mom, Mary (Samantha Smith), so the manipulative God, aka Chuck (Rob Benedict), quickly does the deed. When an angry Sam shoots Chuck, the vengeful deity awakens the dead and unleashes hordes of ghosts and zombies that swarm the good guys, accompanied by the proclamation "Welcome to the end!"

Singer previews the apocalypse to come.

As the world's overseer, Chuck has always found the Winchesters more entertaining than troublesome. Will he relent and save the brothers and Cas from his wrath?

According to Singer, it looks like they'll have to save themselves. "Chuck will not necessarily be onscreen a lot, but [he will] return to play an integral role next year, creating interesting twists and turns," he notes.

Some of those creatures attacking the hunters are familiar from former episodes, including the pilot's ghostly Woman in White and Season 1's Bloody Mary. Should we anticipate more returnees now that it's the beginning of the end?

Absolutely! Expect a "best of" parade of characters from the horror series' long history. "We want to pay off every character we can that viewers have either come to love or hate," the exec says. "This season will be less about big set pieces and more about the problems and personalities of both the living people and the resurrected ghosts that Cas and the Winchester brothers run into."

Will we get one final offbeat meta episode before the series wraps?

Good news. Singer says, "We want to do another episode in the vein of [Season 5's] 'Changing Channels' and [Season 6's] 'The French Mistake' — one of our big, crazy swings." Hmmm…could that mean we're up for another alternate-universe adventure? We'll have to wait and see.

We last saw Jack wake up in the darkness of the Empty, a void that serves as an afterlife for celestial-adjacent beings, where former reaper Billie (Lisa Berry), reincarnated as Death, says she has a proposition for him. Does Death need Jack's help to fight God?

Perhaps. Chuck clearly doesn't like his newest Death. "He may see her as a rival," Singer teases. "What Billie offers Jack will unfold over the course of the year."

What about the version of a series finale Ackles and Padalecki have often discussed — that they want to go out fighting à la Butch Cassidy and the Sundance Kid? Should we forget about a happy ending?

Not necessarily. "Frankly, we don't want it to be a total downer," Singer says. "That would disappoint us, and the fans as well." But will the brothers leave the world they've worked so hard to save time and time again in a better place? "I can't promise that the world is all butterflies and sweetness at the end," Singer says.

However, he does vow to give viewers "an emotional season and a real ending," he says. "We won't do an enigmatic ending as in The Sopranos or St. Elsewhere."

Supernatural, 15th and Final Season Premiere, Thursday, October 10, 8/7c, The CW