Ever since the final episode of Stranger Things streamed on Netflix on New Year’s Eve, a fan theory dubbed “Conformity Gate” has been circulating on social media.

It claims that “Episode 8: The Rightside Up” — with a 2-hour and 8-minute runtime — was not the true ending of the series.

Instead, fans believe that the happy ending the Hawkins crew received as they moved on with their lives was actually an illusion created by Vecna (played by Jamie Campbell Bower), and that the true finale, Episode 9, will be released by Netflix on Jan. 7.

Stranger Things fans are calling it Conformity Gate because the conclusion in the epilogue represents a kind of forced conformity that goes against the show's core themes, which include breaking cycles and defying control.

Neither Netflix nor the show’s cocreators, Ross and Matt Duffer, have announced that there will be an Episode 9 of Stranger Things. However, Netflix announced this week that it will release a documentary about the show, One Last Adventure: The Making of Stranger Things 5, on Jan. 12.

Why do fans think another episode is coming on Jan. 7?

There are a few reasons. Netflix teased an upcoming event scheduled for Jan. 7, which takes an early look at the streaming service's upcoming shows and movie titles. This announcement has led some fans to interpret it as a hint about Stranger Things news.

“Sometimes, the universe shows you a sign,” the narrator in the teaser video says. “You can brush it off, call it a coincidence, but I know you got some questions. Lucky you, your future’s on its way, and even when you’re not working, it haunts you. So go on. All you gotta do is ask.”

Fans also believe Jan. 7 is a significant date because it’s Orthodox Christmas. All of the Stranger Things Season 5 episode drops have happened on major holidays: Thanksgiving, Christmas and New Year’s Eve.

The number seven also holds significance for fans because, in the very first episode of Season 1, the Hawkins crew is playing Dungeons & Dragons, and Will Byers (Noah Schnapp) rolls a seven with the game die. “The Demogorgan, it got me,” Will later tells his friend Mike Wheeler (Finn Wolfhard), revealing the game’s outcome. Fast forward to the finale just before the credits roll, and there’s a shot of the die with the number seven side up alongside a Stranger Things “Player’s Manual.”

Why do fans think Episode 9 is coming out?

There are so many Easter eggs, coincidences and inconsistencies in Season 5 of Stranger Things that make it seem as something is not quite right  — and, according to some fans, it’s all a facade created by Vecna.

Fans have also pointed out that Vecna’s common pose is to sit or stand with his hands crossed in the exact same way, much like when he possesses characters like Billy Hargrove (Dacre Montgomery). In the finale, some viewers noticed that almost every single person in the graduation scene had their hands crossed in the exact same way as Vecna.

Others noticed that a prop dial pointer at the base of the transmission tower of the WSQK radio station changed from gray in Episode 1 to red in Episode 5. Color changes in objects can signify that characters are in Vecna’s mind, like when Holly Wheeler (Nell Fisher) and Max Mayfield (Sadie Sink) realized that part of the merry-go-round was actually a different color, allowing them to escape.

An image circulating on social media from the finale appears to show that when the Dungeons & Dragons binders of Max, Lucas, Will, Dustin and Mike are lined up on a shelf,  they spell out “X A LIE,” which led some fans to believe that the defeat of Vecna in Dimension X was a lie too. However, playing the finale back on Netflix, the binders line up to read “X AILE,” which isn’t a word.

Other fans have noticed plot discrepancies, such as why Jim Hopper (David Harbour) is not struggling with the apparent death of Eleven (Millie Bobby Brown), and why no other characters, including Hopper, who returned to being the chief of Hawkins Police, are facing any legal repercussions from their conflict with the military.

What have the Duffer brothers said about an alternate ending?

The U.K. entertainment site Capital Buzz recently asked the Duffer brothers if they had shot multiple endings to the series.

“Oh no,” Matt Duffer said. “I love when people do that, but I’m like, ‘How do you have the time?’ Oh my god! The energy to A, write it, and then shoot it. Are you crazy? No. No.”

What is certain for Stranger Things fans to look forward to — in addition to the behind-the-scenes documentary — is the upcoming animated series, Stranger Things: Tales From '85, and a live-action spin-off that focuses on the rock that gave young Henry Creel his powers in the cave.