On the eve of the second anniversary of the Alien Amnesty Act, Supergirl has to deal with a rising way of anti-alien sentiment.
Tropes in this episode:
- Actual Pacifist: After his father's death, J'onn has found a new direction in life, refusing to fight in any way.
- Adaptational Badass: Otis goes from a Fat Comic Relief to a very dangerous, competent criminal.
- Badass Normal: Mercy and Otis have no powers, but pose a great danger towards Kara nonetheless.
- Borrowed Biometric Bypass: Mercy and Otis cut off Dr. Voz's arm tusks so they can use his DNA to access his labs. They didn't have to do it that way specifically, they just wanted to make an anti-alien statement while they were doing it.
- Bulletproof Vest: Otis wears one to survive being shot by Mercy as part of their Wounded Gazelle Gambit.
- Cliffhanger: Supergirl's clone is responsible for the earthquake in Kaznia, a result of her punching a tunnel beneath the bridge for an unknown purpose.
- Cover-Blowing Superpower: President Marsdin is shot by Otis. Though her invulnerability lets her shrug it off, Mercy and Otis hid a camera that recorded the incident, which briefly shows her Glamour Failure and exposes her as an alien to the public.
- Crazy-Prepared: When Supergirl tries to stop Mercy and Otis from stealing the EMP, they use a sonic weapon to disorient her, a non-lethal blaster that knocks her out a window, then gravity cuffs on her legs to keep her from flying. When she recovers, they use a firebomb to threaten Dr. Voz so she'll be forced to protect him, allowing them to escape.
- Designated Girl Fight: Alex and Mercy face off during the assassination attempt on President Marsdin. They're roughly even, forcing Mercy to end the fight by tossing a firebomb at Alex, who then has to contain the blast in a shield while Mercy escapes.
- Does This Remind You of Anything?: The debate at the alien support group is identical to the debate around passing in the transgender community.
- EMP: Mercy and Otis steal an EMP from Dr. Voz's lab as preparation for their assault on Camp David. Brainy has a countermeasure in place that immediately restores power, but it was meant to be a distraction anyway.
- Family-Unfriendly Violence: Fiona's murder is one of the more graphic and disturbing that the series has presented.
- Glamour: Lena is selling image inducers that allow aliens to pass for human.
- Glamour Failure: President Marsdin's human disguise briefly falters when she is shot, enough for a camera to record it and expose her true nature to the public.
- Go-Karting with Bowser: While visiting her mother in custody, Lena plays chess with her.
- Gratuitous Russian: The passengers of the Kasnian train, saved by Supergirl, thank her in Russian, even giving her a bottle of vodka as a gift. James initially wonders if she was in Russia. Apparently, Russian is an official language in Kasnia, possibly standing in for Belarus.
- Internal Reveal: The public at large learns that President Marsdin is an alien.
- Jerkass Realization: After being confronted by Brainy, Alex realizes that despite his own faults, she had been way too hard on him, because he isn't Winn.
- Kick the Dog: Agent Liberty kills Fiona for basically no reason, other than being an alien.
- Knight Templar: Mercy tells Kara in all honesty that she thinks she is the good guy.
- Mama Bear: Lillian Luthor smiles at the revelation that Lena used the information she gave her about Bruno Mannheim to get Mannheim arrested. It's implied that Lillian figured out that Lena was recording her, and used the opportunity to get revenge on someone she blamed for Lex going off the deep end.
- Motor Mouth: Nia Nal, to the point where Kara is almost creeped out on how much she reminds her of herself.
- Mugged for Disguise: Mercy and Otis mug a couple of DEO guards for their uniforms.
- Mythology Gag: The episode title is named after a comic book storyline by the same name, though it was unrelated ("Superman: American Alien" is about a younger Clark as a teenager, growing into his powers and out of his actually kinda dickish Golden Age portrayal and into the big blue boy scout we know).
- No Social Skills: Brainy, to the extreme frustration of Alex.
- Off Screen Moment Of Awesome: Superman has reunited with the survivors of Krypton on Argo - but it's a reunion we do not get to see.
- Pragmatic Villainy: Lillian Luthor implies that she despises Bruno Mannheim for turning Lex bad and Superman for bringing Lex to justice. While Lillian wouldn't mind seeing Superman suffer, she knows that going after the Man of Steel would most likely end badly for her. Going after Corrupt Corporate Executive Mannheim is another matter entirely.
- Psychopathic Manchild: Otis shows a huge amount of childish glee and immaturity during his scenes.
- Put on a Bus:
- Superman is taking a vacation to visit the surviving Kryptonians on Argo, leaving Supergirl to pull double duty guarding National City and Superman's other duties.
- Sam Arias has left National City to run L-Corp Northeast.
- Reformed Criminal: Lillian claims to have turned over a new leaf. It's questionable whether or not she is genuine.
- Sacrificial Lamb: Fiona is introduced as the leader of the alien support group J'onn attends, and the two seem to be good friends. This is to give her death more impact when Agent Liberty senselessly kills her.
- Siblings in Crime: Mercy and Otis.
- So Proud of You: A quite twisted version, as Lillian actually seems to feel this way about Lena outsmarting her, knocking down her king on the chessboard as a visual shorthand for "you got me". Alternately, she may have been pleased that Lena was smart enough to record her words about Bruno Mannheim and use them not only to get Jimmy Olsen off the hook but get revenge on someone Lillian blamed for turning Lex into a villain.
- Superman Stays Out of Gotham: Unlike Season 3, in which Superman's general absence was noticeable during the Reign and Argo City arcs, a line of dialogue establishes that he is off-world for now (visiting Argo), which explains why he is nowhere to be seen as the public begins to turn against aliens.
- Take That!: The anti-alien people who want to commit terrorist actions and hate crimes communicate with Agent Liberty and Mercy through 4chan, saying things like "Earth First".
- Taking the Bullet: A Secret Service agent attempts this for President Marsdin when Otis shoots at her, but she pushes the agent out of the way because the bullets won't kill her. Though noble, Mercy and Otis were counting on this, as it allows them to expose her as an alien to the public.
- Tempting Fate: Kara tells James that she feels like she finally has everything in her life under control. In comes Mercy Graves.
- Took a Level in Cheerfulness: Kara, though to the point where she point blank refuses to acknowledge any racist sentiments against aliens until they're literally right in front of her (anti-alien message boards).
- Wounded Gazelle Gambit:
- Mercy shoots Otis as they're escaping Camp David, causing him to fall off a cliff. Otis calls for Supergirl's help, forcing Supergirl to abandon Mercy to save him. Then it's revealed he's wearing a bulletproof vest, the two having arranged this beforehand so Mercy could escape.
- Also, Lena acts as if she wants to reconnect with her mother, solely to record something that will help her incriminate Bruno Mannheim.
