Every Single Thing You Need to Know About Stranger Things Before Watching Season 2

A bloodthirsty monster escapes from a remote laboratory in Hawkins, IN, in 1983, killing any scientist who gets in its way. Shortly after escaping, it encounters young Will Byers (Noah Schnapp), who's riding his bike home alone at night after playing a game of Dungeons & Dragons with his best friends — Mike (Finn Wolfhard), Dustin (Gaten Matarazzo), and Lucas (Caleb McLaughlin). Will tries to escape the monster by running into the shed in his backyard and threatening it with a gun. As the light bulb in the shed flickers on and off, Will disappears, quite literally, into thin air.

Will's very frazzled mom, Joyce (Winona Ryder), returns home the next morning after a long shift at work and discovers that her son is missing. She and Will's brother, Jonathan (Charlie Heaton), frantically call around searching for Will, but to no avail. Eventually Joyce reports the disappearance to the town's police chief, Jim Hopper (David Harbour) — a slacker and alcoholic who refuses to believe Will vanished.

While the search for Will rages on, a young girl sneaks into the back of Benny's Diner (with a shaved head and wearing nothing but a hospital gown). Benny finds her stealing a cheeseburger in the kitchen and tries to calm her down before calling social workers to come pick her up. Unfortunately, a nefarious team of men — presumably from the same lab the monster escaped from — arrive at Benny's instead. They immediately murder the diner owner, and in the commotion Eleven is able to escape.

Will's friends, who have taken it upon themselves to find him since the cops won't, run into her shivering in the woods. She can't speak, but they take her under their wing anyway. She soon reveals to them that she has strange powers (like being able to move things with her mind and making a school bully pee his pants) and that she knows where Will is — attempting to hide from a monster, whom the boys dub the "Demogorgon." She was experimented on at the same lab and is now on the run from "bad people." Her powers do have a limit, however, and if she exerts herself too much, she gets a bloody nose and starts to faint.

Joyce and Chief Hopper discover later in the series that Eleven's mom participated in tests for Dr. Brenner while she was pregnant, which is likely to blame for her abilities. Although doctors told the woman that she had a miscarriage, Brenner actually took the baby away. Eleven's mom was left incapacitated from whatever tests were performed on her.

Hawkins High School's most popular guy, Steve (Joe Keery), has his sights set on romancing Mike's older sister, Nancy (Natalia Dyer). She resists him at first, until he invites her to a pool party at his house one night. She brings along her stick-in-the-mud friend Barb (Shannon Purser) but soon ditches her to hook up with Steve upstairs. Jonathan is in the woods taking photos of them (yeah, not creepy at all . . . ) and manages to catch the Demogorgon appearing next to Barb after she cuts her finger (it can smell blood). It drags her, screaming, into the shadowy realm where it lives. Nancy tells her mom that Barb has vanished just like Will, and the town starts to take an interest in what's going on (although mostly everyone just ignores the plight of poor Barb; rude).

Because Jonathan can't catch a break, Nancy finds his creepy photos from that night. After getting pushed around by Steve (who is clearly threatened by Jonathan's obvious crush on Nancy), Nancy sees the Demogorgon in the photo with Barb. Together the teenagers start their own hunt for whatever took both Barb and Will.

The Demogorgon's lair is in a space known as "the Upside Down," which looks almost identical to our reality, only darker, mistier, and full of really gross goo (not even Chip and Joanna Gaines could fix this mess). Eleven confirms that this is where Will and Barb are likely being kept, which frustrates Mike, Dustin, and Lucas since they don't believe her. We also discover more about her life at the lab through disturbing flashbacks. She'd been raised there and experimented on by Dr. Brenner (Matthew Modine), who was a sort of father figure to her while also pushing her powers to their limits (and essentially forcing her to act out and kill some of the lab's employees). She spent the first years of her life in a cell, cut off from a normal childhood. Fortunately, the boys take pity on her and let her hide out in Mike's basement, since his parents never go down there.

Chief Hopper is finally convinced that Joyce might be onto something about Will being taken when he looks into Hawkins Laboratory. He gets bad vibes from Dr. Brenner and then realizes they destroyed security footage from the night Will disappeared (the Byers family's house is nearby).

Meanwhile, Joyce becomes convinced that Will is trying to communicate with her via electricity. She strings up a ton of Christmas lights in the living room and paints one letter of the alphabet to correspond with each light on the wall (like a DIY Ouija board). She asks if Will is alive, and he answers "yes." He also tells her he's not safe, which is immediately followed by the lights going crazy and the wall of the house seeming to stretch out (as if something is trying to get through).

Joyce attempts to tell Hopper her theory, but a body of a young boy who looks exactly like Will is pulled out of the local quarry. Hopper calls off the case, but Joyce insists that it's not her son ("My boy! My boy!"). Luckily, Hopper gets suspicious and checks out the body himself. After stabbing Will's corpse with surgical tools in the morgue, stuffing comes pouring out. It's merely a highly realistic fake. Will is still alive, somewhere, and now Hopper is fully committed to finding him.

He sneaks back into the lab and finds the gooey entrance to the Upside Down in the basement. Guards arrive and knock him out, and he wakes up in his trailer, which he promptly tears apart looking for a bug (there is one, of course). Although the cops find Barb's car at a train station, he realizes a giant conspiracy has taken over Hawkins and promises Joyce they'll get to the bottom of it.

Eleven tells the boys she'll bring them to the Upside Down but backs out at the last second because she doesn't want to put them in danger. Lucas reams her out for the deception, causing a rift in the group. Eleven, pissed off, lifts him up in the air with her mind and slams him back on the ground. She quickly runs away, fearing that she's ruined her friendship with them.

Jonathan and Nancy also go into the woods looking for the Demogorgon but get separated. Nancy stumbles upon an entrance to the Upside Down in a tree and goes in by herself. Jonathan saves her and agrees to spend the night at her house because she's scared. Nothing happens, but Steve sees them together and publicly mocks Nancy the next day. Steve and Jonathan brawl, with the latter getting arrested by police.

Desperate and all by herself, Eleven strolls into a supermarket and casually steals all of the Eggo waffles it has to offer. She causes a huge scene when, after the manager yells at her, she shatters the store's windows and walks out. At the same time, Mike and Dustin run into some bullies from school, who threaten to cut out Dustin's teeth unless he jumps into the quarry (which is way too far down to survive). Mike agrees, though, and jumps. Fortunately, Eleven arrives just in time and stops him from falling with her powers and mentally knocks the bullies around. They get a Walkie Talkie message from Lucas, who's since forgiven Eleven, that Dr. Brenner and more guys from the lab are on their way to get Eleven.

Hopper hears about Eleven's powers because of the scenes she's been making in town and seeks out the group (who narrowly evade Brenner and his men in an epic chase scene). Eleven, the boys, Hopper, Nancy, and Jonathan then all team up to pool their resources and help find Will (Barb has been all but forgotten at this point, but whatever). Eleven reveals that she can locate Will if she's in a sensory-deprivation tank, so the gang rigs one up in the school gym. The good news? She finds him. The bad news? Barb is really, really dead (and it looks like her dead body is being used as a nest for the Demogorgon's eggs).

Hopper leaves the kids to break into Hawkins Laboratory with Joyce once again, while Jonathan and Nancy try to lure the Demogorgon to Joyce's house. Hopper and Joyce manage to get inside the Upside Down and save Will (he has a nasty tentacle down his throat but is otherwise unscathed). Nancy and Jonathan are joined at the Byers house by a remorseful Steve, and together the three booby trap every inch of the home. They manage to light the monster on fire, and it disappears — is it really dead?

Brenner and his men show up to Hawkins High after Hopper leaves, but Eleven makes quick work of most of them. Their bloody remains attract the Demogorgon, who takes out the rest of the men and seemingly kills Brenner (there's never a shot of his dead body, though, so we can't be sure if he's truly dead). Eleven passes out from using too much of her powers, so the boys fight off the monster with Lucas's slingshot in the meantime. Right as it's about to eat them for dinner (or whatever it plans on doing with them), Eleven reawakens and uses the last of her powers to blow up the Demogorogon — and herself. Everyone is devastated.

Season one ends by flashing forward one month later. The boys, including a recovered Will, are once again playing Dungeons & Dragons in Mike's basement. Despite the chemistry between Nancy and Jonathan, she's gone back to dating Steve. Jonathan and Will are then seen having Christmas dinner with Joyce, but Will leaves to go to the bathroom. He looks at himself in the mirror, distraught, before coughing up a slug-like creature, which climbs down the pipe.

Hopper puts on a brave face at the police station's Christmas party, but it's clear that he's still processing everything that happened. He leaves the party early to drop off a box of Eggos near a tree in the woods, which implies Eleven might be alive after all. Her survival is left ambiguous, but she's alive and (kinda) well in the season two trailer, so there's still hope!