It's been two years since Stranger Things Season 2 arrived on Netflix, and that's a long time to remember every big win and terrible loss, even for the most dedicated fans. For those needing a refresher before Season 3 drops on July 4 but don’t have time to binge-watch Seasons 1 and 2, here’s a brief refresher.

The Fates of the Mind Flayer & the Upside Down

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In Season 2, the Mind Flayer, a parasitic eldritch entity intent on consuming entire dimensions, took over Will Byers and almost destroyed Hawkins. Meanwhile, Eleven ran away from the cabin in the woods where Sheriff Hopper was hiding her and made her way to Chicago, where she met Kali/Eight, another test subject that had escaped Hawkins National Laboratory.

Season 2 also introduced four new characters: Max Mayfield, a spunky redhead who quickly integrated into the group; Billy Hargrove, her abusive stepbrother; Bob, Joyce Byers’ now-deceased boyfriend; and Murray, a conspiracy theorist who knew the truth about Hawkins Laboratory's experiments.

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At the end of Season 2, Will Byers was seemingly purged of the Mind Flayer, Eleven returned to Hawkins and closed the portal connecting the Upside Down with our world. She was also officially adopted by Hopper and accepted into the town’s normal life. Additionally, Lucas and Max had seemingly started dating, as had Jonathan and Nancy.

Although Eleven closed the portal and Will’s connection seemed to have been severed, the final shot of Season 2 showed the Mind Flayer’s arachnid shape looming over the school dance. Despite being trapped in the Upside Down, The Mind Flayer was definitely seeking a way back into Hawkins.

What Do We Know About Season 3 So Far?

Season 3 takes place during the summer holidays of 1985, and it seems to be leading up to a 4th of July celebration to end all of the others. This means that school is out, and the kids will have the long days and the short nights of summer to fight The Mind Flayer. The central hub that was Hawkins’ Laboratory seems to have been replaced with Starcourt Mall, which for the summer season comes complete with a carnival.

Several of the characters seem to have also gotten jobs, with Steve now working at an ice-cream parlor called Scoops Ahoy and Billy lifeguarding at the local swimming pool.

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This season will also see the addition of Robin (Maya Hawke), Steve's colleague at Scoops Ahoy; Bruce (Jake Busey), a journalist; Heather (Francesca Reale, a lifeguard; and several more characters, including a mysterious goonish-looking antagonist.

Who Is Billy Hargrove?

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Introduced in Season 2, Billy is Max's abusive stepbrother. Although he wasn't particularly well-developed in that season, the newest trailer shows Billy getting possessed by The Mind Flayer, and it's hinted that he will be a formidable Big Bad this season and the conduit for bringing the Upside Down back into Hawkins.

Don't Forget Lucas' Sister, Erica

Lucas’ little sister became a fan favorite with her deadpan snarker sass aimed mostly at her brother and his friends. She wasn’t in any particular danger in Season 2, but she seems to be playing a bigger role this season, teaming up with Dustin, Steve and Robin in what looks like a midnight run to outpace some sinister black helicopters.

What Happened to Hawkins National Laboratory?

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Hawkins National Laboratory was a secretive scientific research site whose main focus was carrying ESP experiments on kidnapped children for the purposes of using them as against the Russians in the Cold War. There were at least eleven test subjects.

One of them was Eleven’s biological mother, Terry Ives, who signed up to test psychedelic drugs while she was (unknowingly) pregnant with Eleven, whom she had called Jane. The lab kidnapped her baby girl. Terry unsuccessfully sued the lab, and then she tried to take Eleven/Jane away. However, before she could hug her daughter, Dr. Brenner captured her and fried her brain through electroconvulsive therapy.

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Two children were introduced in the comic book series SIX, including the eponymous test subject, who possessed precognitive abilities, and Three/Ricky, who had the ability to manipulate emotions. After them came Eight/Kali, who was born in London and kidnapped as a toddler. Her powers are mostly psychic. She's clairvoyant and a master of illusions. When her abilities grew strong enough, she used them to escape the lab, and after a while, she formed her own band of misfits hellbent on taking revenge on every perpetrator of Hawkins’ experiments. In Season 2, she briefly bonded with Eleven, but the latter decided to return to Hawkins instead of joining Eight’s gang.

Eleven is, seemingly, the last of the test subjects. In Season 1, she accidentally opened a rift into the Upside Down and contacted a Demogorgon. Instead of closing the rift, Hawkins National Laboratory opted to explore the Upside Down, allowing it to spread tunnels under the town of Hawkins. In Season 2, The Mind Flayer used these tunnels to launch a demodog invasion into Hawkins, and was only repelled when the protagonists blew up the tunnel network.

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Hawkins Laboratory was finally closed when it was proven the facility was responsible for the death of Barbara Holland in Season 1, with the character finally getting justice.

Created by the Duffer Brothers, Stranger Things stars Winona Ryder, David Harbour, Finn Wolfhard, Millie Bobby Brown, Gaten Matarazzo, Caleb McLaughlin, Noah Schnapp, Natalia Dyer, Charlie Heaton, Joe Keery, Priah Ferguson, Cary Elwes, Jake Busey and Maya Thurman-Hawke. Season 3 arrives July 4 on Netflix.