When Jeremiah Danvers is rescued from a Cadmus convoy, Alex and Kara are relieved to have their father home. A wedge is driven between the sisters, however, when Mon-El expresses his concerns about something not being right about Jeremiah and Kara thinks he may be right!
The film Captain America: The Winter Soldier (loved one of the hero returns as a sleeper agent with an artificial arm.) and Superman: The Movie (the scene with Kara saving the train.)
Unfortunately, the whole episode is built around a rather unlikely conceit - that the usually oblivious Mon-El is the only one to smell a rat regarding Jeremiah's return being too convenient. (Then again, this could be a sign that he isn't the shallow idiot he's acted like since arriving on Earth...)
So Kara and Alex go after Jeremiah alone, without any other DEO agents as back-up? Not even Mon-El?
The scenes in which Mon-El and Winn bond at the bar are great ones for Jeremy Jordan and Chris Wood.
Saving trains that are in danger of being derailed is a standard feat of the various Superman family members. Perhaps the most famous example of this is in Superman: The Movie but it has occurred in various comics as well.
Cadmus utilizes lead-line vehicles to prevent x-ray vision from being used to see through them.
Kara's heat-vision radiation signature is used to track the Cadmus nuclear fusion bomb.
Jerimiah's right arm was enhanced with cybernetics in the same way as Cyborg Superman's body. He was also given some kind of ability to resist Martian telepathy.
(After kissing Mon-El.)
Kara: Gosh, it's so nice to do that without breaking the guy's nose.
Mon-El: How many times did that happen?
Kara: (giggling, embarrassed) Ummm... less than five.
Mon-El: So four.
(Mon-El has just bluntly revealed that he and Kara are a couple to J'onn and Alex..)
Kara: Can we just pretend like that never happened?
J'onn: I'd like nothing more but unfortunately, as your supervisor, I have to ask you to report to HR
(Kara laughs. She quickly realizes she's the only one who is.)
Kara: Wait... you're serious?!
J'onn: Kara, you're dating a co-worker.
Kara: That's not... wait... we have an HR?
J'onn: (pointing to Mon-El) Walk this puppy down to the second floor and fill out all the forms Pam gives you. In triplicate.
(J'onn walks off.)
Alex: Oh. And you're going to have to attend a mandatory sexual harassment seminar.
(Alex walks off leaving Kara and Mon-El alone. Kara is clearly not happy. Mon-El is wearing the expression of every boyfriend who has just realized that he is going to pay for this.)
Mon-El: It's going to be a rough sparring session for me.
Kara: (sarcastically) You think?
Mon-El: Okay. I'm going to warm up.
Mon-El: Sir, as a scientist you have to believe in questioning. That's all I was trying to do in there. I'm sorry if I hurt-
Jeremiah: I know who you are.
Mon-El: ... and?
Jeremiah: That's it. I know who you are. And I doubt Kara would like the truth.
Kara and Mon-El did spend the night together.
Before Mon-El wakes up, Supergirl stops five armed robberies, delivered a litter of puppies and helped one tugboat captain bring in a ship.
Kara has accidentally broken the noses of four men whom she kissed in the past.
On Daxam, it was customary to throw parties whenever a couple got together.
The DEO does have an HR Department and a sexual harassment policy. They don't prohibit co-workers from dating but do require it be strictly monitored.
Jeremiah Danvers was last seen in 207.
Jeremiah Danvers claims that he and Hank Henshaw were found by Cadmus. He was then forced to keep Henshaw alive and perform the procedures that turned him into The Cyborg Superman. He did such a good job he was put to work enhancing other agents.
Jeremiah Danvers' right hand was extensively damaged as punishment for helping Kara and Mon-El to escape from Cadmus.
Mon-El points out that the DEO has never picked up an alert of Cadmus activity unless they were caught red-handed or were intentionally trying to be noticed.
Jeremiah Danvers claims that Cadmus has a nuclear fusion bomb, built using the energy they mined from Kara's heat-vision blasts while she was their hostage. Their plan is to blow up National City and blame it on alien terrorists.
Jeremiah Danvers claims to know the truth about who Mon-El is, privately, when speaking to him.
Winn gave Mon-El his Netflix password.
Jeremiah claims he only hacked the DEO mainframe to read the old case files of what his daughters had done.
Winn discovers that Jeremiah stole the DEO's registry of every alien in the USA.
Jeremiah struck some kind of bargain with Lillian Luthor for his help.
Cadmus is at work building some kind of armored ship.
The Kryptonite Factor
Honestly, the only way for this episode to work is for the most paranoid characters to suddenly become trusting and the most naive characters to suddenly become paranoid.
The Bottom Line
A typically flat mid-season filler episode that does nothing but temporarily throw a monkey wrench into the relationship drama without really changing anything. Still, the scenes of Winn and Mon-El bonding are fun and the bits of Melissa Benoist and Chris Wood playing cute are good. The script definitely needed a few more rewrites, however.