The following contains spoilers for season 2 of Stranger Things.

The second season of Stranger Things certainly upped the ante on everything. From new big baddie the Shadow Monster to a system of supernatural tunnels underneath Hawkins, the binge-worthy Netflix show certainly delivered the goods when it came to giving fans ’80s-tinged demogorgon realness. At Vulture Festival LA, the Duffer Brothers Matt and Ross took the dais with producer Shawn Levy as well as actors Finn Wolfhard, Paul Reiser, and Linnea Berthelsen to talk about the latest season and tease fans about the third season — which may or may not be happening (I am betting it is).

During the Vulture confab, the cast and crew gathered on stage in what seemed to be a behind-the-scenes look at the second season as they simply shared anecdotes about making the sophomore season including auditions, creating the new story, introducing new characters, developing fan favorites and other trivia tidbits to feed the massive crowd of Stranger Things diehards.

Highlights included how the hurdles they had to jump to use the Ghostbusters costumes and how Matt and Ross actually talked to Ivan Reitman to get permission to use the iconic jumpsuits. Speaking to that, the brothers admitted that the show’s nerdy pop culture stories and details are a result of actual arguments coming out of the writers’ room including the discussion between the four core boys on who should be which Ghostbuster as well as the great Three Musketeers candy bar debate. “A debate about candy bars can get heated,” joked Matt Duffer.

Vulture Festival

Other surprising details about the season had a lot to do with a change of characters and narrative such as Berthelsen’s Kali was originally written as a thirtysomething man (imagine that) and that the bromance we all fell in love with between Dustin and Steve wasn’t originally in the script. Even with some of the new characters like Sean Astin’s fan-favorite Bob was supposed to die earlier in the season but ended up staying on longer because Astin helped developed him into a vital character to the story.

As for casting Reiser for the new character of Dr. Sam Owens, it was a no-brainer. “Two of my favorite movies of all time are Aliens and Diner,” said Matt Duffer. That said, the Duffers said that they conceived the character for Reiser.

But one of the most memorable characters of the new season was Berthelsen’s Kali, Eleven’s sister from another mister with supernatural powers. She was introduced in the very first episode which included a car chase and a display of her powers. The scene was remarkably different for Stranger Things and the Duffer Brothers admitted that they wanted it to be a departure for them. They also had different intentions for that opening scene.

“We just wanted to do a car chase – it’s really childish,” said Matt Duffer. “But it builds from there — I wanted people to think ‘Did I click on the wrong show?’ This introduced a major new character and explored different tones and opened it up to a new world.”

Vulture Festival

This led to talking about the polarizing standalone seventh episode of the season titled “The Lost Sister.” People were all up in their feelings about the episode that reunited Millie Bobby Brown’s Eleven with Kali (a.k.a. Eight). The show left the confines of Hawkins and into the big city where we were introduced to Kali and her punk rock friends. The culty Warriors vibe the Duffer Brothers were trying to accomplish was seen by many as kitschy and off-putting. Even so, the cast and crew stood by the episode and how it diversified the narrative.

Ross Duffer said they like “experimenting with form” when it came to storytelling and leaving Hawkins and the Upside Down. “We got excited about taking a breather before we dive back in,” he said. “And it annoyed some people.”

Levy stood by the episode saying “Whether people love or don’t love episode seven, we always knew the boys wanted to try something bold. It allowed Eleven to learn about her powers and gain more —which we need for episode nine. Her going away makes that return at the end of episode eight so powerful.”

Berthelsen adds, “Whether or not you like the episode, it’s really powerful, and it’s about people taking risks.”

Speaking of standalone episodes, Wolfhard joked later on in the panel that, considering the boys’ musical talents, there might just be a musical episode in the future. “I have I have my idea that we [do a] crossover with Hamilton.” Considering there is a song in Hamilton titled “Yorktown (The World Turned Upside Down)” this is a mash-up that just might happen.

This brought us to whether or not Kali would return for season three — or if there will be a season three at all.

“We are [in] very early days on season three and we’re still figuring it out,” said Ross Duffer. But after saying this he looked around and said “I probably wasn’t supposed to say that.” He then reeled it in and said in a joking panic “That’s not official, that wasn’t an official announcement — we’re just working on it, just for our own amusement…for fun!”

But going back to Kali, Matt Duffer said that it would make sense to move ahead because of her character. “It feels weird to me that we wouldn’t solve [Kali’s] storyline,” he said. “I would say chances are very high she comes back.”

Wolfhard adds, “Maybe if you guys like it, there will be a third season!”