Last time on Stranger Things 3: Have a Coke and a smile.

Cold Open: Dustin (Gaten Matarazzo), Steve (Joe Keery), Robin (Maya Hawke), and Erica (Priah Ferguson) don't have very much time to process the Russians' science experiment happening in front of their eyes, as the soldier Steve knocked out has regained consciousness and alerted his friends to the presence of intruders. Time for a chase! It's clear they all won't make it out and avoid capture, so Steve and Robin stay behind and allow Dustin and Erica to exit through the air ducts.

Back at the hospital, Will (Noah Schnapp) feels his flayer-sense goes off — he knows the Mind Flayer is close, and we do too since the last episode ended with the monster reconstituting itself from the goo formerly known as the Hawkins Post editorial staff.

Upstairs, Nancy (Natalia Dyer) is chased by the flesh monster — and like T-1000, it can melt itself down to fit under doors. Bad news for Nancy, since she's hiding in one of the hospital rooms. Is this the end of our potential Final Girl? The monster closes in on Nancy's face — she's given the full Ripley fear shot from Alien 3 — and just as it goes in for the kill... Eleven (Millie Bobby Brown) arrives to mess it up and throw it right out the window. America, f--- yeah!

Injured, the monster slinks away through the sewer grate as the kids watch on in horror. But the best cold open of the season isn't done just yet: We see the flesh monster find itself back at the abandoned steel mill, where it absorbs into a larger host version of the Mind Flayer's right-side-up form. Billy (Dacre Montgomery) and Heather (Francesca Reale) watch along with blank faces of approval.

Hopper and Joyce: As Mayor Kline (Cary Elwes) prepares for the town's Fourth of July celebration, Darth Drago comes knocking — he wants to know where Hopper is hiding and gives the mayor just one day to find Hawkins' police chief. If only Mayor Kline were watching this very episode! Hopper (David Harbour), Joyce (Winona Ryder), and Alexei the Russian scientist are laying low with Murray (Brett Gelman) watching cartoons and providing Burger King with some righteous product placement. (Eat Whoppers, kids!) The kidnapped Russian is a hostile witness, at first, but he soon realizes something Hopper knew first: It doesn't matter whether Alexei tells them the secrets of the Russian base under Starcourt Mall or not; the Russians will think he talked and kill him regardless. Alexei, welcome to Team Jopper.

With Murray acting as translator, Alexei explains why the Russians came to Hawkins in the first place: The city has a gate to the Upside Down that was previously opened, making it easier for them to break through the "still healing" door between worlds. Bad news we already know but Hopper and Joyce didn't: The door is already opening.

Upon hearing that information, Hopper takes action and calls the answering service for one Dr. Sam Owens (Paul Reiser), the former head of Hawkins Lab who helped Hopper adopt Eleven at the end of Stranger Things 2. Hopper has a message for the operator, and so does Joyce, who thinks Hopper's sense of urgency is lacking: "If you don't want to lose your job, here's what's going to happen. When I hang up, you're going to get up off your ass and go find Owens and tell him what's going on. We don't have time to talk about it and neither does he. He's got to get to Hawkins and bring his men right now!" The cavalry has been notified.

Dustin and Steve and Robin and Erica: In the air ducts, Dustin finally explains the plots of Stranger Things 1 and Stranger Things 2 to Erica, who is dubious of only one part of his story: Lucas' involvement. Little sisters! Adding Erica as a major part of Stranger Things 3 has been a boon for the show, and this entire sequence, which ends with Dustin convincing the coolest kid in Hawkins that she might be — gasp! — a nerd, is the kind of character-building stuff the Duffer brothers are able to do so well.

The high of Dustin and Erica doesn't last too long: Steve is being beaten unconscious as the Russians think he's an American spy. Our hair icon and Robin are tied up like Indiana Jones and his dad in Indiana Jones and the Last Crusade and forced to wait for a "doctor" to come and finish the interrogation. You don't need me to put the "not great, Bob" meme here because we're all thinking it anyway.

Dustin and Erica reach the storage room — will they go back to the surface or help set Steve and Robin free? As we contemplate that obvious answer, Steve regains consciousness and, after a botched escape attempt, has a heartfelt conversation with Robin. It turns out she sat behind him in sophomore history and couldn't help but notice the King of Hawkins High — not that he even knew Robin existed. Fans 'shipping these two will be in heaven after this scene. Maya Hawke has been a highlight through Stranger Things 3, and this moment, shot in close-ups of her and Joe Keery, is a true flex of her talent. It also does a great job reminding the audience of Steve's overall redemption arc. What a sequence!

Anyway, the misty eyes of our captured heroes don't last long. The Russians are back, and the "doctor" they promised arrives with a tool kit of torture devices and a syringe of what we can only call truth serum. He injects.

It works, but Steve and Robin are high as eff and don't provide the Russians with the answers they had hoped. As the "doctor" tries to pry off Steve's fingernail — an alarm sounds. It's a Dustin ex Erica! The kids break in amid the distraction, shock the doctor to unconsciousness, and make a harrowing run for it with Steve and Robin in tow.

Nancy and Jonathan and Mike and Eleven and Lucas and Max and Will: Following their tussle with the Mind Flayer at the hospital, the kids reconvene at House of Hopper. Eleven looks through the Void to find any remaining members of the flayed, and thus his source spot, but they've all gone invisible. In the living room, Mike (Finn Wolfhard) battles with Max (Sadie Sink) over how much voiding Eleven can take — and their discussion degenerates into a referendum on why Mike can't just let Eleven be Eleven (she saved the world twice, as Max cheekily notes; mic drop). Mike? "I don't want her to die looking for the flayed when they've obviously vanished off the face of the Earth. So can we please come up with a new plan? Because I love her and don't want to lose her again."

Pause here for dramatic glances. Mike looooooveessssss Eleven, awwww. Just as soon as that registers with the group, Eleven comes outside. (What did she hear of that conversation? Probably everything, she's clairvoyant!) She's found Billy.

It's a trap, obviously, and Billy's bait — but Eleven has an idea. She goes into the Void and approaches Billy, asking to see what happened. So, he obliges: Billy grabs El's arm and she tumbles through his memories like we've entered Inception. Eleven even ends up on a beach, filled with regret. But soon we realize it's just a memory of young Billy and his mother have a good time. In the distance a storm rages, and Eleven approaches to find Billy's more problematic recollections — an abusive dad, a mom who can't stay, a bully at school calling Billy a "p---y," and ... the Mind Flayer and the abandoned steel factory. Jackpot! Eleven, satisfied, returns to the House of Hopper — or what she thinks is the House of Hopper but is actually just another Inception level. Billy's there, and he makes clear what the plans are: They can all "see" Eleven. "You let us in," Billy says as we're shown the flayed becoming active and leaving the Fourth of July festivities happening around town to head toward the steel mill. "And now you are going to have to let us stay. Don't you see? All this time we've been building it for you. All that work, all that pain. All of it, for you. And now it's time to end it. And we're going to end you, and when you are gone, we're going to end your friends. And then, we're going to end everyone."

Eleven bursts out of the Void with a shout, clutching Mike back in reality. And the flayed? They walk like lemmings toward the Mind Flayer, turning into human goo and absorbing into his body to help the monster grow to its final, massive form. (R.I.P. Heather, Heather's mom, and Mrs. Driscoll.)

Burning Questions: How did it take me six episodes and numerous Eleven trips into the Void for me to realize it's a visual mirror to Jonathan Glazer's Under the Skin with Scarlett Johanasson?

Movie of the Episode: This entire season has been touching on themes first presented in 1956's Invasion of the Body Snatchers — and since this episode seems to have ended that arc (the episode title pretty much calls it: "E Pluribus Unum," out of many, one), let's give it a proper shout-out. The iconic horror thriller was rooted in themes of anti-McCarthyism but also could be read as a takedown of communism — basically, Body Snatchers works as a repudiation of many forms of corrosive groupthink. Stranger Things 3 broadly trods that same terrain. Although politics are not its main concern, this season pretty clearly looks to the past to comment on our current political climate, with Russia acting as the publicly facing boogyman while the corrosive nature of American capitalism and bad faith actors festers beneath the surface, doing the real damage. Or, you know, maybe not. (Invasion of the Body Snatchers is streaming on numerous digital platforms, including Amazon Prime Video.)

Quote of the Episode: Alexei through Murray to Hopper: "He likes your courage. You remind him of a Fat Rambo."

TV Guide Episode Rating: 4.5 out of 5

Stranger Things is now streaming on Netflix.

Up Next: Episode 7, The Bite