Millie Bobby Brown's tenure on "Stranger Things" was supposed to be short-lived, it turns out.
In a new book titled "Stranger Things: Worlds Turned Upside Down," co-creator Ross Duffer said Eleven, Millie's character, was initially supposed to vanish after dismissing Demogorgon in the finale of the first season.
"Eleven was going to sacrifice herself to save the day," Ross revealed in the book, via the Daily Mail. "That was always the end game."
"But once we realized that the show was potentially going to go on longer than one season, we needed to leave it more up in the air, because deep down we knew the show just wouldn't really work without Eleven," he wrote. "And at that point we knew how special Millie was. If there were going to be more 'Stranger Things,' Eleven had to come back."
Upon the success of the show, more things changed, too. Like Eleven, Joe Keery's character wasn't supposed to last either.
"This Steve character, he was just supposed to be this giant douchebag," Ross said of Joe's Steve Harrington character, adding that he was supposed to be killed off in season one.
Bob Newby, played by Sean Astin, actually did get killed off, but the death came far later than initially planned.
"Bob was always intended to die, but you weren't supposed to be that sad about it," Ross said. "But Sean Astin proved so likable that Bob's death got pushed from episode four to episode eight because we kept wanting to keep him alive."
Ross added, "It was important to us and also to Sean to give him a bit of a hero's death. We wanted him to accomplish something meaningful."
The show itself, while now a massive hit, was far from a slam dunk. In fact, the book revealed that it was rejected 15 to 20 times by multiple studios before Netflix snatched it up.
"A lot of the concerns were based on the fact that this is a show about kids, but it's not a kids' show," Ross's co-creator brother Matt Duffer said in the book. "People couldn't figure that out. The other big thing was that no one wanted a show set in the 1980s. It's funny, the two things that made the show successful were the two things that were red flags for everybody."