Everything That Happens to Billy in Stranger Things Season 3

Warning: This post contains spoilers for Stranger Things season 3.

After making an enemy of himself by bullying our favorite group of Hawkins misfits and beating up Steve (Joe Keery) in season 2 of Stranger Things, Billy (ustinacre Montgomery) seemed due for a redemption arc. But season 3 turned out to be a little more complicated for the Hawkins hunk.

Although Billy’s season 3 storyline culminated in him sacrificing himself to save Eleven (Millie Bobby Brown) from the Mind Flayer monster, the horrors he committed leading up to that moment were some of the worst we’ve seen on the show. Of course, it’s important to note that Billy was possessed by the Mind Flayer for the majority of season — a development that made it difficult to come to a definitive conclusion about his character.

So before you cast your final judgment on Billy, let’s try to make sense of everything that happened to him in Stranger Things season 3.

Chapter One: “Suzie, Do You Copy?”

Billy started the season working as a lifeguard at Hawkins Community Pool, where his shirtless jaunts from the locker room to the lifeguard chair made him the object of every Hawkins housewife’s desire. But his plan to seduce Karen Wheeler (Cara Buono) at the Motel 6 backfires when his windshield is hit by a mysterious slimy object that makes him swerve off the road and crash into a tree outside of the abandoned Brimborn Steel Works. After getting out of the car to assess the damage, Billy is violently dragged into the basement of the factory by an unseen force that we later learn is none other than the Mind Flayer.

Even though El closed the gate to the Upside Down in season 2, the part of the Mind Flayer that had attached itself to Will is apparently still kicking around Hawkins.

Chapter Two: “The Mall Rats”

The season’s second episode picks up right where the premiere left off, with an injured and terrified Billy emerging from the steel works basement and sprinting to his car before driving to the nearest phone booth and dialing 911. But when the emergency operator picks up, flashbacks of what the Mind Flayer had just done to him keep him silent. Billy stumbles out of the phone booth as red lightning flashed across the sky — a surefire sign that he had somehow become linked to the Upside Down — to find a group of mysterious figures walking toward him. The group’s leader then steps forward to reveal that he is a carbon copy of Billy himself. Flash-forward to later in the episode when a distressed Billy recalls the previous night’s events and remembers his Upside Down self’s message. “I want you to build,” he tells Billy. “What you see.”

After coming back to himself on the lifeguard chair, Billy flees to the pool’s showers as the red mark on his arm begins to pulse and spread, indicating that the Mind Flayer has activated itself inside him. It is then that fellow lifeguard Heather (Francesca Reale) comes to check on him, and Billy — despite managing to leave Karen unharmed earlier in the episode — is no longer able to resist the Mind Flayer’s hold on him.

Flayed Billy kidnaps Heather and takes her to the old steel works, where he “feeds” her to the Mind Flayer to allow it to take control of her.

Chapter Three: “The Case of the Missing Lifeguard”

It should come as no surprise that the first person in Hawkins to realize there’s something wrong with Billy is Eleven, who catches a glimpse of what he was doing to Heather after she and Max decide to use her telepathic powers to spy on him. Unfortunately, the part of the Mind Flayer inside Billy also caught a glimpse of El and recognized her as the one who had closed the gate to the Upside Down.

El and Max (Sadie Sink) quickly set off on a mission to figure out what’s going on. First stop: Billy’s bathroom, where they discover both the remains of an ice bath — a nod to the Mind Flayer’s penchant for seeking out cooler temperatures — and Heather’s bloodied lifeguard whistle. El then tunes into Heather’s headspace and sees her submerged in Billy’s ice-filled bathtub begging for help before she was sucked away into its watery depths. Just like with Billy, it seems that Heather’s true self had become trapped inside of her after the Mind Flayer invaded her body.

This becomes clearer in the final scene of the episode, when flayed Billy and Heather violently attack Heather’s parents with the intent of recruiting them to join the Mind Flayer’s hive mind army.

Chapter Four: “The Sauna Test”

After flayed Billy and Heather finish feeding Heather’s parents to the Mind Flayer, Billy takes some time off from terrorizing the people of Hawkins to report for duty at the pool. But once Will (Noah Schnapp), Mike (Finn Wolfhard) and Lucas (Caleb McLaughlin) relay the news of the Mind Flayer’s return to El and Max, the kids have no choice but to take matters into their own hands.

To figure out if the Mind Flayer has attached itself to Billy, the gang comes up with a plan to trap him in the pool’s sauna room and turn up the heat to see if it would trigger the Mind Flayer. Once they get him inside, it seemed at first like it was the real Billy begging Max for help and insisting that the bad things he had done weren’t his fault. But as the heat rises, the Mind Flayer becomes fully activated and forces Billy to smash through the sauna’s glass window with a shard of tile and try to stab Max.

The physical effects of the Mind Flayer’s possession — a web of black veins — then appear all over Billy’s body and, in a fit of superhuman strength, he bursts through the chained door and almost gets the best of El in a head-to-head fight. Luckily, thanks to an assist from Mike, El is able to use her powers to throw Billy through the brick wall of the pool house, where he runs off into the night.

Back at the steel works, Billy gives Heather a rundown of the night: “It was her. She knows now. She knows about me. She could’ve killed me.”

“Yes, but not us,” Heather ominously responds before the camera pans out to reveal the basement is now full of flayed Hawkins citizens.

Chapter Five: “The Flayed”

Billy doesn’t appear in the Stranger Things season 3’s fifth episode, but the group has a nearly fatal run-in with some of Hawkins’ other flayed residents. Even after Jonathan (Charlie Heaton) and Nancy (Natalia Dyer) manage to take out flayed Tom and Bruce (Jake Busey), their mutilated bodies morph into sentient masses of blood and guts that join together to become a smaller version of the Mind Flayer monster, an incident that demonstrates just how dangerous the Mind Flayer’s abilities are.

Mike also makes it clear that it won’t be enough to burn the Mind Flayer out of Billy like they did with Will in season 2. During a conversation with Will and Lucas, he insists that they need to stop the Mind Flayer itself rather than the people to whom it has attached itself.

Chapter Six: “E Pluribus Unum”

“It’s time,” Billy menacingly announces after the bloody mass that had once been Tom and Bruce rejoins with the main Mind Flayer monster in the basement of the steel works. But time for what, exactly?

As episode 6 progresses, we learn that Billy has returned home after leaving the steel works and is simply hanging out in his room, a move that El and co. quickly determine is a trap. So instead of seeking him out in person, El decides to use her powers to mentally connect with him — just like she did with her mom in season 2 — in hopes of finding the source of the Mind Flayer.

After diving into Billy’s mind, El finds herself inside one of Billy’s best childhood memories — showing off his surfing skills to his mom on a beach in California — in a scene that gives off major Inception vibes. She then spots the red lightning storm that signifies the Mind Flayer’s presence raging in the distance and begins to walk toward it. As she makes her way closer to the source, Billy’s memories worsen, seeming to indicate that the Mind Flayer is feeding off of the darkest moments of his life to maintain control over him.

Eventually, El makes it to the memory of the night that the Mind Flayer possessed him and discovers that the source was the steel works. But when she tries to emerge from Billy’s mind, it’s clear that something has gone wrong. When El removes her blindfold, she is no longer surrounded by her friends in Hopper’s cabin. Instead, Billy — acting as the mouth-piece of the Mind Flayer — is now there with her.

“You shouldn’t have looked for me. Because now I see you,” he tells her, revealing that she had accidentally created a connection between the Mind Flayer’s mind and her own by entering Billy’s. “Now we can all see you. You let us in. And now, you are going to have to let us stay. Don’t you see? All this time, we’ve been building it. We’ve been building it for you. All that work, all that pain, all of it for you. And now it’s time. Time to end it. And we are going to end you. And when you are gone, we are going to end your friends. And then we are going to end everyone.”

El manages to use her powers to throw Billy and get back to her friends. But what she hasn’t seen is that, at that very moment, all of the flayed citizens of Hawkins are returning to the steel works to form one massive Mind Flayer monster. Turns out El was the Mind Flayer’s main target all along.

Chapter 7: “The Bite”

Billy doesn’t appear until midway through episode 7, but his words come back to haunt Eleven when the now-massive Mind Flayer monster shows up at Hopper’s cabin. El manages to fight the creature off, but not before it severely injures her by “biting” her on the leg.

The group cleans up El’s wound at a grocery store and leaves to go find Dustin at Starcourt Mall. But Billy is hot on their trail. After finding El’s blood — which appears to be infused with essence of Mind Flayer — on the supermarket floor, the Mind Flayer’s influence over him seems to grow even stronger.

Chapter 8: “The Battle of Starcourt”

And now, for the grand finale.

After El drains her powers by using them to remove the piece of the Mind Flayer that was inside of her bite wound, she is left defenseless against both Billy and the Mind Flayer monster. So when Billy is waiting for the group outside of Starcourt Mall, after cutting Nancy’s ignition cable, they have no choice but to retreat back inside. The kids are then left with nowhere to go when the Mind Flayer monster bursts through the mall’s ceiling and traps them in the food court.

We next see Billy chasing after El, Mike and Max after Steve heroically rams his car to allow the rest of the group to escape. Billy catches up with the trio in a back hallway and knocks Mike and Max out before hoisting El over his shoulder and carrying her back out to the food court to feed to the Mind Flayer monster.

But just when it seems like there may be no hope for El, she begins describing the memory she had seen of Billy surfing on the beach while his mother watched. El’s recollection of Billy’s happiest memory somehow breaks through the Mind Flayer’s hold on him, and his true self reemerges long enough for him to sacrifice himself to save El and give Joyce time to close the gate to the Upside Down.

Proving that his final moments were his and his alone, Billy’s last words to his sister Max are a simple apology for everything he has done: “I’m sorry.”

As things stand now, it doesn’t seem like there’s any way that Billy could possibly return in season 4. But hey, stranger things have happened.