Mon-el wakes up naked and alone in Kara’s bed. She had jet off to get them coffee. They are happy and kissy but she wants to keep it quiet for now. He blatantly disregards that as they walk into the DEO and he announces it to everyone. J’onn tells them to go to HR and Alex stands by laughing. Before Kara can walk away though Winn announces Cadmus activity. Supergirl and J’onn stop the convoy and save Jeremiah. They bring him back to headquarters and Alex is ecstatic to see him. She evaluates him while he explains the last 15 or so years of his life. Mon-el naturally runs in “as soon as he hears.” Also, Cadmus is doing things.
Winn breaks down the science tip about Cadmus and Jeremiah gives him advice on how to trace their new weapon. Eliza walks in and has a big reunion with her long lost husband. Mon-el mentions to Kara that something seems off but she doesn’t listen.
Family dinner has Kara and Alex setting the table when there’s a knock on the door. It’s Maggie. Alex comes out to her dad and he “flatters” Maggie. Mon-el also turns up. Jeremiah talks about all his years spent dreaming of his happy family and Eliza talks about learning each other again.
J’onn turns up and they talk about coming home. Jeremiah says that he wants to join the DEO. Everyone embraces it, except Mon-el. He thinks the whole thing seems fishy but no one listens. Kara pulls him aside to call him on his complete disregard for her wishes and overall lack of respect. She tells him to leave and Jeremiah walks him out. In the hall, he tells Mon-el that he knows who he really is and that Kara might not like it.
Mon-el meets up with Winn at the bar to express his concerns about Jeremiah. He explains his suspicions and Winn agrees to keep an eye out, in exchange for a favor. He wants Mon-el to promise to be good to Kara. Winn’s new alien girlfriend stops by to say hello.
J’onn gives Jeremiah a tour of the DEO and talks about his daughters. They go their separate ways and Jeremiah immediately starts fiddling with the mainframe. Winn sees and reports back to Mon-el. They confront Kara who during a meeting mentions it to Jeremiah. He plays it off like he’s trying to catch up on their lives.
Alex and Kara fight about trusting Jeremiah and Kara automatically taking Mon-el’s side. Alex tells Kara to act like part of the family. Winn and Mon-el talk in the bar about his relationship with Kara. The alert goes off. Winn found the bomb.
The DEO moves in on the location but the warehouse is empty. Alex uses her radio to reach out to J’onn and Jeremiah but the latter ignores her. He heads to the mainframe to mess with the files. He’s a cyborg. He fights J’onn and knocks out Winn. He’s working for Cadmus. Alex, Kara and the other agents in the field head back.
J’onn and Winn are in the med bay. Alex doesn’t want to believe Jeremiah did this. J’onn explains that he’s enhanced. Alex says that Cadmus will pay. They need to find him. Winn happens to have set up a tracker. Jeremiah reports back to Hank Henshaw and Lillian Luthor but before they get away Alex and Supergirl show up.
The bad guy team blows out a train bridge so Kara goes to fix that while Alex chases the others. Kara saves the train and Alex confronts her father. He tells her that he did it for her. She wants to bring him in but he says not alive. She lines up the shot and yells at him. He tells her that she is the best part of him. She can’t do it. He runs while she cries alone in the woods.
J’onn wants to move forward, find out what they are up against. Alex talks to her mother. Maggie comes to Alex’s apartment and holds her while she cries. Mon-el finally tells Kara he’s listening. Kara’s phone rings. Winn found out what Jeremiah stole. The alien registry. Cadmus now has a list of all the aliens in the country, and a machine to get rid of them.
Why is Mon-el the one noticing all this stuff? And why is Kara still dating him when she clearly sees all of the terrible character traits he displays and is unapologetic about? Maggie is a detective. She should be the one noticing that Jeremiah seems off. She should also get more than 30 seconds of consoling Alex, considering plywood get like three minutes to talk to Kara after he said he wasn’t going to talk. Mon-el is bullshit and I don’t want to watch him. Also, where was James?
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