Previously on Supergirl, Alex voluntarily got her mind erased to protect Supergirl’s true identity, Kelly went with Alex when she thought she was going to get to adopt a baby but then it fell through, Lena and Kara found out about Kaznian Kara aka the Red Daughter, and Kara went to tell the president about Lex’s nefarious plans and instead of getting a Pulitzer she got black-bagged.
We open in Midvale, in 2007, when adorable teens Alex and Kara are walking through the forest, clapping to some music on their iPod. Kara is trying to convince Alex she can’t go to college, but Alex is sure Kara will make new friends. Kara says no one will understand her like Alex does, but their conversation is interrupted when Kara’s clapping gets a little too enthusiastic and she accidentally thunder-claps them off the cliff.
Before she hits the ground though, Alex wakes with a start. It seems she fell asleep watching TV after her heart-to-heart with Kelly. Because Kelly is still there.
Alex tells her that she had a dream or a memory of Kara, and Kelly thinks it’s probably her brain changing; she has suffered a trauma re: adoption, and her brain is making connections with the parts of her life deeply affected by adoption before. Specifically, Kara.
Alex can tell something is happening in her brain, because she’s starting to feel off again, like she did during the interrogations. Right after her mind was wiped, though she doesn’t know that part. All she knows is that is has to do with Kara.
But before she can figure out what’s going on in her brain, Brainy calls. She’s needed at the DEO.
When the black bag is removed from Kara’s head, she finds herself in a room with some men who clearly don’t know what they’re up against. She easily takes them out, but as soon as she opens the door to make her escape, Kaznian Kara is there with some Kryptonite to knock her out.
Back at the DEO, Brainy and Lena tell Alex about how Lockwood took the Harun-El, Kara thinks Lockwood and Lex are connected, and about the found a Supergirl clone called the Red Daughter. They break to do their tasks, Alex to find the Red Daughter, Brainy to get J’onn to save the aliens being rounded up for Lex to harness their powers, and also to tell Dreamer loves her. That last task got Lena good.
Lena is going to talk to Lockwood and see if she can find out where Lex is. Before she leaves, Alex asks Lena where Kara is, and Lena assures her she’s just in DC and is totally fine.
But in actuality, Kara is slightly less than fine, being held captive by a girl who has her face and an intense wig.
Kara tries to reason with her, to tell her Lex is a liar and will turn on her, but the Red Daughter is sure Kara is the villain here, protecting this corrupt country rife with ugliness and gluttony. But while she’s giving her hero’s speech, the Red Daughter is starting to feel weakened by the Kryptonite. And lucky for Kara, she’s built up an ever-so-slightly higher tolerance to it, so she uses this opportunity to break free and fly away.
Kara shows up at J’onn’s door, injured and so… defeated. She really thought she was at the finish line, evidence in hand, putting down her cape and winning the fight with her research and journalism. But then everything fell apart around her. What’s more, Lex knows that Kara is Supergirl, which means Alex is in more danger than usual, and she really wants to tell Alex the truth so she knows the stakes. But J’onn warns her against that. Telling Alex the truth after J’onn so carefully tucked it away in her brain could cause her to go insane. The only way she can know is if the walls he built in her brain come down on their own. Kara is so, so sad.
Brainy comes by and tells them what everyone is up to, so Kara runs off to join the fight.
Before Lena goes to see Lockwood like she said, she goes to see her mother, who is in her lab. Because Lena bought her prison and got her a weekend off. Because of course she did. Lena slaps a baby truth seeker alien on her mother’s arm and starts asking her questions.
Lena starts with a test and asks about a high school boyfriend. Lillian blurts out that she paid him to leave Lena alone. Since this confirmed Lena’s suspicions, she starts asking her about a procedure to extract the Harun-El. Lillian knows she can do it, and as an incentive to do it quickly, Lena informs her mother that she has poisoned her and she has 24 hours to do as she’s told or she won’t get Lena’s antidote.
Before Lena can leave, Lillian blurts out one more truth, but this is one Lena didn’t suspect: Lillian says she loves her.
After leaving her mother, Lena heads to a parking garage to confront Lockwood, which is a role reversal I’m into. Lena asks where Lex is, and it quickly becomes clear that he has no idea that Lex Luthor has been the puppetmaster of his life for the past few years. Lockwood looks a little ill, his hair is falling out, and he’s mad. He starts yelling at Lena, but she yells back, saying he’s dooming humanity.
After she leaves him and gets back in James’ car, Lena tells James that Lockwood is deteriorating because of the untested Harun-El he stole. She almost calls the mission a bust, but then Lockwood speeds away and they realize he could lead them somewhere useful.
J’onn, Brainy, and Dreamer follow one of Nia’s visions to a shipping company where they find a lot of the aliens rounded up in raids being packed into shipping trucks. Dreamer has a plan.
But J’onn and Brainy think it might be too dangerous. So instead, J’onn is going to do a fly-over to see what he can see before they decide what their next move is. But while he’s gone, Brainy is so frazzled from almost confessing his love to Nia that he agrees to do things her way and they head into the fray with Brainy pretending to be Lockwood and Nia pretending to be his prisoner.
At the DEO, Alex is startled when Supergirl swoops in to tell her that the President is working with Lex. But Alex trusts her, so she immediately shuts off the cameras so they can work in private. Alex starts using sunlamps to get Supergirl back up to full strength, talking about what it’s like to absorb the sun’s energy, when Col. Haley bursts in, horrified to see Public Enemy #1 in her Director’s lab.
Alex tells her the whole thing about the Supergirl copy and the President being corrupt Haley is immediately on board with taking them all down.
Brainy and Dreamer’s ruse is found out almost immediately and they’re split up, despite their protesting. Brainy is tortured and worried about Dreamer and eventually his ancestral memories flood his brain and his emotional boxes get smashed to bits and he’s essentially, in his words, rebooted. Suddenly he’s cold and emotionless. He’s not our Brainy anymore. He’s Brainiac 5.
Alex, Kara, and Haley exchange info and brainstorm and realize that they have to find the Red Daughter before she causes any more havoc in Supergirl’s name.
They find an address, and Supergirl insists on going alone. Alex thinks it’s weird that Supergirl is so insistent she not join her on this mission, but she hangs back.
When Supergirl gets to the Red Daughter’s apartment, it’s eerily similar to Kara’s loft. As she slowly looks around, she realizes she’s been stalked but good. #YouonLifetime
At the compound, Brainy’s voice is deep and scary, and despite his humanity switch being entirely turned off, he does concede to J’onn that they can go save Dreamer, because she might be useful. When he finds her though, he doesn’t save her. He tells her to astral project from the other side once she’s fully kidnapped, then knocks J’onn out so he’ll get caught too, and walks coldly away.
Lockwood is still deteriorating, so he gives himself another injection of Harun-El and storms into a safe house to confront Otis, who confirms everything Lena said about Lex pulling his puppet strings. Lena and James creep in and watch from the rafters as Lockwood realizes that no one else believes in his cause like he does, and that all Lex wants is to fake an attack from Kaznia so he can be the hero.
Otis says that now that Lockwood knows, he has to die, and a fight breaks out. James tries to intervene, but his head starts to hurt and he’s incapacitated.
Kara is looking at a sketch of Alex in the Red Daughter’s journal, along with a photo of Mikhail, when Alex busts in, confused as to why the apartment looks so much like Kara’s. She realizes that you can see into Kara’s loft from this apartment, and starts to panic; she hadn’t considered her normal human sister could be this caught up in all this. She describes the way she worries about Kara feeling like part of her heart is just running around in the world, unprotected.
As Alex tries to collect herself, Supergirl puts her hand on Alex’s, comforting her. Before Alex can examine why it doesn’t feel as weird as it should that her coworker is holding her hand, her mom calls her and tells her that Kara is there. Alex is relieved to hear that, until Supergirl panics and says that Eliza is not safe.
Supergirl flies to Midvale as fast as she can, and the Red Daughter is there, furious at the life Kara had that she didn’t. Kara tries to reason with her, she knows the Red Daughter is having doubts about Lex, but she snaps and says his name is Alex.
Supergirl tries one more time to connect with the Red Daughter, mentioning Mikhail, but instead of being the bonding agent she hoped, it sets her off, because she thinks Americans killed the little boy she cared about. The Red Daughter suits up in her new supersuit, complete with helmet, and flies outside. Supergirl is hot on her tail, and they do some pretty epic fighting in the sky. But the Red Daughter has some kind of purple lightning situation, and punches Supergirl with it so hard, possibly into next Tuesday? Because suddenly it’s dark. And they fall to the ground, where they fight some more.
Alex rolls up on her motorcycle, and when she sees Supergirl getting punched, memories start flooding back to her. She remembers moments in their childhood when Kara would use her powers. She remembers pivotal moments they shared as adults. She remembers the moment Kara saved the falling plane she was on. Laughter and tears, pizza toasts and the time she fell off the clip but Kara saved her. She remembers everything.
So she runs to save Supergirl. To save her sister. But by the time she gets there, the Red Daughter has already heard Supergirl’s heart stop beating and flown away. She does stop for a moment as she watches Alex cry over her sister’s unmoving body.
Alex tries to listen for a heartbeat, pleading with her little sister, she remembers, to come back to her. Alex says she knows her Kara, and Kara doesn’t quit.
Eliza watches and cries as her oldest daughter cradles her youngest. Two pieces of her heart, breaking right in front of her. Between sobs, Alex insists Kara will be fine. She’s only not healing because there’s not enough sun. But there’s sunlight in everything! So she starts shoving handfuls of grass into Kara’s hands, begging her to use the sunlight in the leaves to heal herself. It felt very, “He can’t see without his glasses” and it hurt my feelings.
But then streaks of brightness start to glow around them, and Eliza tells Alex to look. Kara is pulling in the sunlight.
And that’s how Kara always gets back up when she gets knocked down, isn’t it? No matter how many times she’s defeated, how many people tell her she can’t, whether it’s running into issues at CatCo or red tape at the DEO, fighting family members or losing friends, every time it seems that by all measures, Kara Danvers should be defeated by the darkness, she starts pulling in the sunlight. Even though sometimes Alex needs to remind her she can.
When Kara finally wakes up again, and she sees her sister looking down at her with love in her eyes despite being in the Supersuit, she says, “I’ve missed you.” The sisters are reunited. Finally.
Back in Lena’s lab, Lena is going to have Lillian extract the Harun-El so James won’t be in pain anymore, but James wants to keep his strength because the season finale is next week and Rao knows he’ll need it. So instead, they give him another dose. To thank her mother for all her help today, she gives her the antidote.
While debriefing and reconnecting, Alex and Kara get a call from Col. Haley. Lex’s plan has come to fruition. The president is on TV, saying Kaznia attacked, lead by Supergirl, and that Lex Luthor saved the day.
Things look darker than they have in long time, but as long as she has Alex by her side, Kara will be able to pull the sunlight and get through it.
See you next week for the Season Four finale!