The second-to-last episode of Westworld season 4 aired on Sunday, setting the stage for next week's finale. It caps off with a surprising twist -- this time involving Christina -- our brunette Dolores look-alike whose story took yet another turn.

In other news, this season's big bad, Chalores, has been replaced by her second-in-command. Let's run through what else happened in episode 7, including who's still standing on both sides as we head into the final episode. 

A door to The Sublime

The episode starts with Bernard and Maeve pulling up to the futuristic Hoover Dam facility we saw in episode 1 -- the one William acquired with help from our first, nameless fly victim of the season. But eventually, the show reveals we are actually somewhere else… in The Sublime. When Bernard convened with Akecheta in The Sublime back in episode 3, he viewed these events before they took place (or it's one of the many paths he viewed that could potentially happen, I guess). 

Bernard reveals to Maeve -- a version of her he's whipped up -- that "the hydroelectric server farm" they're looking at houses The Sublime. (Also called The Valley Beyond, The Sublime is a digital plane of existence we saw a bunch of Westworld hosts enter in season 2, leaving their physical bodies behind. Maeve's daughter is one of them.) In season 2, Dolores sent The Sublime -- and those in it -- somewhere out of reach. Turns out, it was here. Bernard uses the key he possesses to open the door.

Bernard tells Maeve that he's been down every possible path, and the outcome is always the same: extinction for both hosts and humans. He tells her they could escape that fate by uploading themselves to The Sublime. Maeve takes him up on the offer, and Bernard asks if that's what she would really say, or if that's just his impression of her. 

Then, those events pretty much repeat in the real world (with the addition of some more on-screen action involving a big red robot). Bernard and Maeve arrive at the facility, Bernard once again reveals it holds the Sublime and opens the door using his key. But he doesn't tell Maeve the truth about their ill-fated quest. Instead, he says that "If we get to her tower, we can save them as well as ourselves."

Chalores is shutting down the cities

Next, we spy Chalores, host William and a host version of Caleb. Like the last version of Caleb who got his neck snapped so unkindly last week, this one knows his daughter, Frankie, is alive. Chalores is a nickname for Charlotte Hale. In the past, Dolores made copies of herself -- the "self" that exists in her pearl -- and put one into a host version of Hale.

Chalores tells William to give them a minute, and then she reveals to Caleb that she's shutting down "the cities." (There are more than the one we've seen, I guess). She plans to stick humans in cold storage, mirroring how the hosts in Westworld were treated. She leaves Caleb in his confinement, and tells a surprised William she's calling the human world quits because of the host/outlier issue. "If I don't do this today, there'll be less of us tomorrow," she says.

An already stressed-out host William is not happy about this news. Later, we see him visit human William again. In a long, icy spiel, human William tells his host doppelgänger that "culture doesn't survive, cockroaches do." He tells his host counterpart that if he could, he'd pull the plug on the whole world. "Only one of us needs to do what must be done," he tells the host. Host William says he understands, then stabs him. 

"Dolores. Please."

In this episode, Teddy confirms something many have probably suspected from the start: Christina is Dolores. But then the show piles on a new mystery: the version of Christina/Dolores we've been seeing in Hale's new world this season isn't actually there in the flesh. I'm still trying to wrap my head around this one.

The "Christina equals Dolores" reveal comes relatively early on in the episode. Teddy tells Christina that he and she are "reflections of the people who made us." He then calls her Dolores. At this point, I'm still viewing her as being the Dolores robot from last season, with a memory-wiped mind courtesy of the Rehoboam machine. After learning from Teddy that her kind is less susceptible to death, she gets into a bath, drowns and instantly regains consciousness. 

Later, Christina pays a visit to Olympiad Entertainment, where she uses her storytelling abilities to get the human writers to destroy their "stories" (putting what we've learned from past episodes together, I'm pretty sure these stories are the "pre-scripted loops" humans are traveling in). We see Christina and Teddy wander through Olympiad at the same time as Stubbs and Frankie. Dolores and Teddy walk through a doorway, and then we see Stubbs and Frankie emerge a second later out of the same doorway. Strange. Shouldn't the good guys have bumped into each other?

Near the end of the episode, chaos reigns outside (more on that later), and Christina/Dolores tries to intervene. Teddy tells Christina that people can't see her. Christina asks why, and he reluctantly gives it up: "You're not in this world," he says, "It's real, but you're not."

Caleb and Frankie reunite

After Maeve and Bernard regroup with C/Frankie, C's girlfriend Odina and Stubbs at the abandoned '20s theme park, the squad is ready to enter Chalores' city. 

Once there, they split up -- Odina grabs a boat, Bernard and Maeve set out to confront Chalores at her tower, and Frankie and Stubbs head to Caleb at Olympiad. Bernard reveals to Stubbs that Stubbs isn't going to make it.

Thanks to Christina/Dolores' intervention, Caleb makes it out of his holding cell before Stubbs and C/Frankie arrive. Once they do, a traumatized Caleb ambushes them, locking Stubbs in the confined space and pinning Frankie up against a wall. But Caleb realizes that she's his real daughter soon enough, and the reunion is sweet. This long-awaited scene didn't disappoint. 

A showdown between Maeve and Chalores

We've known since episode 5 that Chalores' plan for her kind is for them to eventually "transcend" -- undergo a procedure where they abandon their host bodies and, as she says in this episode, "evolve into the species that we were meant to become." Their pearls (aka, their minds) are taken out of their heads and placed at the top of tall, white machines. In the latest episode, she sends a message to the hosts that it's time to ditch their current bodies for good.

Maeve and Bernard approach Chalores in her tower, and they split up. But before they do, Bernard admits to Maeve what he's been hiding from her -- "No matter what we do, we can't win," he says. "There's no way to save this world. Everyone here is going to die. But we can save one tiny part of it." He asks Maeve if she's still willing to fight, and she shows him a small smile before continuing on. 

Maeve finds Chalores about to transcend -- a drone host holding a whirring device near her head. Chalores grabs the device and she and Maeve battle it out. They tumble outside and continue to fight in shallow water. Then Maeve is shot in the head by host William.  Next, the host turns on his creator, offering just a few words before also shooting Chalores in the head.

We see Bernard, who's up in Chalores' tower and recording himself speaking on what looks like a tablet. He cryptically says, "If you choose to give her that choice, you can't miss. Reach with your left hand." By the end of this episode, we still don't know who the message is for.

Host William arrives and shoots Bernard in the head. He also rejigs Chalores' sound-producing tower, causing "every man and woman and child -- host and human -- to fight until no one remains but the cockroaches." Given that the humans are controlled by the sounds, he must have ordered the humans to turn on the hosts.

Who's left standing

The show pivots to Frankie, Stubbs and Caleb, and we see people around them begin to fight each other violently. The three of them manage to escape the frenzy, but Frankie takes a bullet to her abdomen. 

On the other side of the fight, host William is pretty much our new big bad as we head into the finale.

Lingering questions:

• In last week's episode, Frankie caught on to Bernard's attempts to copy her and her friends using tech Chalores put in the '20s theme park. (He didn't deny it… or explain why.) This, combined with the fact that the door to The Sublime is sitting wide open has me thinking -- Are copies of some humans (maybe those who visited the park) somehow going to end up in The Sublime?

• How is Teddy back this season? At first, I thought he must have been a host created by Chalores, like William. But now it seems like he may not physically exist in Chalores' new world either.

• Where did Maya, the roommate, go?

• Is Bernard really gone? It seems like no one can actually die on this show, but Bernard's exit seemed more final than, say, Maeve's. We see him follow Charlie, his son as part of his backstory, through a door. We also hear his voice repeat what he said to Akecheta in the Sublime: "In every scenario, I die…" It seems to nail home that he was making a real sacrifice by carrying through with the plan.