Lena is able use the Harun-El to synthesize a formula to exorcise Reign from Sam. With the Worldkillers defeated, Supergirl decides to take an extended sabbatical from saving Earth to go back to Argo to be with her mother, Alura. Meanwhile, J'onn is concerned about his father accepting his inevitable death from his dementia, and is livid to find out that the gun manufacturer who makes DEO weapons has been making modified versions of them for civilian use... especially since one of them found their way into the hands of a criminal.
Tropes:
- The Bad Guy Wins: Selena and her followers escape to Earth, stranding Kara and Mon-El on Argo.
- Bait the Dog: J'onn is very happy about his father being extremely lucid during the past weeks...only for M'yrnn to reveal that this temporary clarity is the last phase before his demise.
- Batman Gambit: Selena's deciding vote to give Kara the Harun-El Rock is revealed to be one. Reign is defeated, so Kara will go back to Argo... giving an opportunity for Selena and her followers to steal Kara's ship and begin her conquest of Earth in person.
- Both Sides Have a Point: As Lena points out to James, there is an argument to be made for gun ownership for self-defense, but she's also willing to see the other side of the issue.
- Broken Aesop: J'onn decides to work against the proliferation of guns by having the DEO get rid of theirs and switch to non-lethal weaponry developed by Winn. While Winn is a sci-fi genius who's developed such things as bullets that shoot energy nets, in real life non-lethal weapons technology is nowhere near advanced enough for law enforcement agencies to rely solely on it.
- Brought Down to Normal: It wasn't made explicit in the last episode, but Kara and Mon-El don't have their powers on Argo. Not that Kara minds, she finds the experience extremely refreshing. Mon-El gives his Legion ring to Kara so she can at least fly.
- But Now I Must Go: Kara decides to leave Earth to spend some time on Argo with her people. Mon-El accompanies her.
- Call-Back: Kara tells Mon-El about her dream of him from the season premiere while they’re in a similar area on Argo and even wearing the exact same outfits.
- Cliffhanger: The episode ends with Selena and her cult arriving on Earth and conjuring another Fortress of Sanctuary. Meanwhile, Sam seems to be suffering side effects from being freed from Reign.
- Disc-One Final Boss: Reign is dispatched within the first two minutes of the episode, leaving Selena to step forth as the true Big Bad.
- Face Death with Dignity: M'yrnn is aware of the fact that his illness is reaching its final stage and is at peace with it.
- First-World Problems: The citizens of Argo consider a misplaced lawn decoration a major tragedy
- Fish out of Water: Kara is having difficulty adjusting on Argo and can't leave behind her superhero instincts.
- Going Postal: The gunman is a former member of a law firm who snapped after his wife left him for being a workaholic while the firm kept passing him over for promotion.
- Green Rocks: Lena discovers that the Harun-El isn't just a curative rock, but has a wide array of potential uses. She doesn't get a chance to explain before the episode ends.
- Hidden Depths: Who would have thought the slightly ditzy Eve Tessmacher would've studied Nuclear Physics at Yale? Which makes you wonder why she is content working at CatCo. Lena picks her up as an assistant. This is a Mythology Gag to the 1978 Superman: The Movie, which likewise revealed Eve to be a scientific genius who only pretended to be ditzy.
- Internal Reveal:
- All of Kara's friends learn about her mother and many of her people still being alive.
- Kara learns the real reason Mon-El stayed behind.
- Selena's role as Priestess of the Worldkillers is exposed to the people of Argo.
- Ironic Echo: James comes to the rescue of a police officer, who doesn't object in the slightest. Two episodes earlier, in "The Fanatical", James had to deal with cops assuming he was a villain and aiming their weapons at him rather than the real bad guys.
- Literal Split Personality: Lena's cure causes Reign to physically separate from Sam before evaporating into glowing dust.
- Mass "Oh, Crap!": The reaction on Argo when they find out Selena and her followers have stolen Kara and Mon-El's ship to go to Earth, especially since the Worldkiller sigil is burned into the ground where the ship once was.
- Motive Misidentification: The gunman is initially spotted near a bank and is assumed to have been attempting a robbery. When his identity is tracked down later, they realize he doesn't fit the profile. The confusion is cleared up when he posts a manifesto about his treatment at a law firm, revealing him to be a disgruntled former employee.
- Mundanger: J'onn and the DEO's plot for this episode covers the very plausible threat of a vengeful employee shooting up his former place of business. It's one of the only times the DEO has been shown engaged in a mission that is not related to aliens. J'onn even notes that it's not a normal part of their job, but they had to get involved due to their weapons supplier selling the guns to civilians.
- Mythology Gag:
- The Black Rock of Harun-El acts very similarly to Black Kryptonite -seen in Smallville, Superman III and Supergirl stories Girl Power and The Condemned Legionnaires- after Lena has melted some to inject into Reign, separating her from Sam before causing her to disintegrate.
- James calls for Miss Tessmacher in the same tone as Lex in Superman: The Movie, much like Cat Grant did back in the Season Two premiere.
- Tessmacher is revealed to be a scientific genius, much like the original version of the character in Superman: The Movie.
- Tessmacher ends the episode as an assistant to a Luthor once more.
- Never Trust a Trailer: The trailers seem to imply that Supergirl has gone back to Argo while Reign is still a problem, even though the last scene of the previous episode is them about to fight. In fact, Reign is dispatched fairly quickly and the problem Supergirl isn't around to handle is DEO weapons making their way into the hands of criminals. It's accurate in a meta sense, though, as the ending has three evil Kryptonians arrive on Earth while Supergirl and Mon-El are stranded on Argo.
- "Not So Different" Remark: The DEO's weapons manufacturer tries to pull this card on James, claiming that selling weapons is no different than CatCo selling newspapers.
- Old Friend: Thara Ak-Var, Kara's childhood friend.
- Properly Paranoid: Kara is ill at ease on Argo, feeling something isn't right, especially after a mysterious hooded figure is seen running away after a construction tower falls down on in the market. Considering Councilwoman Selena is also the Priestess of the Worldkillers, she's right to worry.
- Screw This, I'm Out of Here!: When J'onn announces that he plans to have the DEO begin using non-lethal weapons, some agents walk out.
- Shout-Out:
- The title itself seems to be one to The Wizard of Oz.
- Spoiled by the Format: Reign is defeated... and there's still two episodes left in the season. There's a catch, especially since Selena, the Priestess behind the Worldkillers, is still on Argo. Turns out she still has followers hidden within Argo and escapes to Earth at the end, leaving Kara and Mon-El on Argo without a ship.
- Stranger in a Familiar Land: While she eventually turned out to be right with her paranoia, Kara had a difficult time adjusting back to her Kryptonian home.
- Superman Stays Out of Gotham: Or, rather, Argo City. Despite the fact that Alura is Kal-El's aunt, and thus just as much a member of his family as Kara, no mention is made of Superman having been notified about the survival of Argo City, much less being given a chance to travel there with his cousin for a family reunion. Made even more obvious when his alter ego, Clark Kent, is mentioned by name later in the episode.
- There Are No Coincidences: Kara espouses this view when she thinks the construction accident is a deliberate act of sabotage. Alura and Thara think she's simply paranoid since she always had to be on-guard on Earth, while here accidents do happen. Kara turns out to be right, of course, even though the accident is blamed on a faulty piece of equipment.
- Thou Shalt Not Kill: J'onn decides to get rid of all lethal DEO weapons at the end of the episode.
- Tragic Villain: Arthur Willis, the Villain of the Week for the Earth subplot. A man with mental problems, whose wife left him for working too much and who then got fired from his job for several outbursts. He plans on taking revenge on his former employers via a deadly rampage, but J'onn is able to convince him to stand down.
- A Very Special Episode: The subplot on Earth deals with America's gun control debate.
- We Need a Distraction: A member of the cult reprograms a drone to attack Kara and Mon-El. Even if it fails, the distraction allows Selena and the rest of her followers to steal J'onn's ship and escape to Earth, stranding Kara and Mon-El on Argo.
- You Are Better Than You Think You Are: J'onn is able to convince Arthur Willis to give up his plans of mass murder and surrender by appealing to his humanity.
