Source: Entertainment Weekly

A big part of Stranger Things season 5 was tying up loose ends. Why was Noah Schnapp’s Will Byers taken to the Upside Down all the way back in season 1? What even is the Upside Down? These were two of the biggest questions series creators Matt and Ross Duffer hoped to answer by presenting their legions of fans around the world with a proper conclusion to the story that began in 2016.

To do that, the brotherly duo revisited specific episodes from past seasons.

Season 2 in particular influenced season 5 “in a big way,” Matt tells Entertainment Weekly, “but also we talked a lot about season 1. That’s where it all began. So a lot about season 5 is bringing everything full circle as much as we can.”

If you’re looking to refresh your memory of past events in the lead-up to Stranger Things 5, but perhaps don’t necessarily want to re-binge watch the first four seasons, here are the key episodes the Duffers referenced in crafting this finale story.

Winona Ryder, Millie Bobby Brown, and David Harbour in ‘Stranger Things’ season 1 episode “The Bathtub”.

You might remember this episode, which takes place well after the disappearance of Will, as the one when Eleven (Millie Bobby Brown) telekinetically flips a car through the air as the gang continues to dodge Dr. Martin Brenner (Matthew Modine) and his goons from Hawkins Lab.

More importantly, this is the moment when Eleven figures out a way to telepathically search for Will. Inspired by the bathtub in the Byers household, she tasks her friends with building her own sensory deprivation tank, which they set up in the gym at Hawkins Middle School.

Upon entering the psychic void, she finds the remains of Barb (Shannon Purser), as well as Will hiding inside the warped Upside Down version of Castle Byers.

A lot goes down in the season 1 finale. Nancy (Natalia Dyer) and Jonathan (Charlie Heaton) try to trap a Demogorgon that invades the Byers house, which is reminiscent of a sequence coming in season 5. It’s also the episode where Joyce (Winona Ryder) and Hopper (David Harbour) enter the Upside Down and find Will unresponsive with a tentacle down his throat.

As the Duffers point out, they revisit these season 1 moments over the course of the final season. It’s no spoiler to say that Netflix already revealed the opening five minutes, which goes back to explore more of what happened to Will in season 1. The clip reveals Vecna (Jamie Campbell Bower) put that tentacle down his throat to pump something into the boy.

“We’ve always wanted to explain what Will was doing in that basement, why he is alive, why this vine is attached to his throat. These are all loose ends that we’ve never been able to explain,” Ross comments.

Season 2 really begins Will’s journey to grapple with the lasting effects of his exposure to the Upside Down. “Will the Wise” is one Matt points to. It’s when Will’s episodes — in which he has visions of the Mind Flayer pouring its shadow tentacles inside of him — become more frequent and intense.

Will opens up to Joyce about what he’s experiencing, leading to a scene in which his mom draws a warm bath only for Will to recoil. “He likes it cold,” Will says — “he” being the Mind Flayer.

Elsewhere, Nancy and Jonathan visit the remains of Hawkins Lab, which at this point still has a gaping portal open to the Upside Down that can’t seem to close. It’s also the episode where Eleven has a vision of her mother, Terry Ives (Aimee Mullins), and Hopper discovers a vast network of underground tunnels, thanks to Will’s drawings.

An important piece of lore: Will reveals to the others that he can see everything that the Mind Flayer does. He begins spying on the shadow creature’s movements, though his friends fear the Mind Flayer using this connection against them. Will uses this newfound ability to track Hopper’s movements in the underground tunnels.

Another notable development is that Eleven finds her mother, who’s in a catatonic state. She communicates with Terry through the void and learns how Brenner stole Elle as a baby. When Terry learned the truth, she tracked her daughter down to Brenner’s lab but was forcibly subjected to electroshock therapy that resulted in her current condition.

A scene from October’s Stranger Things 5 trailer shows Vecna, now physically more imposing, meeting Will face to face in the new season. “You are going to help me…one…last…time,” he says.

“The key to that line,” Ross notes, “is to actually not look back at season 1 [but] to look back at season 2, specifically ‘The Spy’ being the most important episode when Will was really working, in a way, for the Mind Flayer.”

Ross is referring to the moment when Will claims to have obtained knowledge of how to defeat the Mind Flayer. So he shows Dr. Sam Owens (Paul Reiser) and his team a location in the underground tunnels he wasn’t supposed to see. It’s revealed later on that the Mind Flayer did use this mental link against the kids by forcing Will to lure the soldiers into a Demogorgon trap.

“A lot of [season 5] was about Henry and his backstory. So ‘Massacre at Hawkins Lab,’ which is episode 7 from season 4,” Matt says, listing off another episode.

This one is uniquely revealing in that the almost 2-hour-long chapter digs into Eleven’s memories of being in Hawkins Lab as a child. It’s the point when viewers learn that Brenner’s mysterious orderly is really One, a.k.a. Henry Creel, a.k.a. Vecna (as we learn by the season’s end).

Not realizing his identity, Eleven telekinetically removes the implanted chip that kept One docile, allowing him to (as the episode’s title suggests) massacre nearly everyone at the facility. In a confrontation, Elle’s powers inadvertently open the first door to the Upside Down, trapping One inside.

Another reason this episode became influential? “The teens are in the Upside Down, and they find that it’s frozen in time,” Ross explains. “That all plays into [season 5] as we get more and more into the Upside Down.”

Stranger Things 5 will release the first four episodes as Volume 1 on Netflix Wednesday at 8 p.m. ET/5 p.m. PT. Episodes 5-7 will then arrive as Volume 2 on Christmas Day at the same time. The series finale, running at around 2 hours, will then drop simultaneously in select movie theaters and on the streaming platform New Year’s Eve at 8 p.m. ET/5 p.m. PT.

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