Kara must help J'onn deal with his painful past and stop an intergalactic incident when a White Martian (whose race destroyed the Green Martian race save for J'onn) takes anti-alien politician Miranda Crane hostage. Meanwhile, Cat's estranged son arrives in National City after Kara sends him a letter claiming that Cat wants to get to know him.
The JLA comics of Grant Morrison and Howard Porter (created The White Martians), The Martian Manhunter comics of John Ostrander (destruction of Martian race following a civil war) and the Justice League animated series (White Martians being an underground race who successfully killed off the Green Martians).
How is it possible for Miranda Crane to be building a reputation on an anti-alien platform when the existence of aliens - apart from Superman and Supergirl - is meant to be a closely guarded secret, at least according to Hank Henshaw in The Pilot, where he said the mission of the DEO was to "cover up the existence of aliens on Earth"?
David Harewood turns in a fantastic performance as J'onn, particularly in the scenes where he talks about the loss of his family. If there's any justice in this world, he'll be freed up to star in a Martian Manhunter spin-off next season.
The imagery of the Martian genocide are visually striking and disturbing, despite their briefness. The design of the White Martian is also quite good, though it's obviously used sparingly except at night to hide the cheap quality of the CGI.
The episode title is taken from the introduction to the 1952 Adventures of Superman TV show, which opened with the phrase "Yes, it’s Superman, strange visitor from another planet who came to earth with powers and abilities far beyond those of mortal men."
Blake Jenner, the actor who plays Adam Foster, is married to Supergirl's actress, Melissa Benoist.
The White Martian race was created by writer Grant Morrison and artist Howard Porter for their run on JLA. White Martians are possess the same wide range of powers as Green Martians but are more war-like in attitude and temperament.
Originally, the Martians were one race capable of asexual reproduction when exposed to fire. The Guardians of the Universe (aka the same aliens who created The Green Lantern Corps), fearing the threat The Martians might become, altered them into two races - White and Green - and instilled a psychic fear of fire that shut down their powers whenever they were exposed to it.
Despite this, war broke out between the two Martian races. Though suffering high losses, the Green Martian race prevailed and most of the White Martians were sent into an extra-dimensional space known as The Still Zone - apparently distinct from the more famous Phantom Zone. Most of the Green Martian race was then killed off by a psychic plague.
Curiously, The White Martians were responsible for superhuman development on Earth being stunted. White Martian scientists migrated to Earth at the dawn of humanity and isolated the so-called metagene that regulated superpowers in humans. They altered the metagene to make it more random, preventing Earthlings from developing into a race with a uniform set of enhanced abilities like the Martians or Kryptonians.
J'onn says that The White Martians were responsible for exterminating his race. The background given here somewhat resembles J'onn's origin story in the Justice League animated series, where J'onn was the sole survivor of another race's attempt to destroy the Green Martians.
Justice League's opening episode, Secret Origins, was loosely based on Grant Morrison's opening arc for JLA, with a race of alien shapeshifters invading Earth and the world's finest heroes joining together to repel it. The aliens in the cartoon were not named as White Martians, but were instead an unspecified parasite race who mimicked the abilities of species they conquered. Still, they absorbed the Martians powers and were depicted as a race that dwelled underground - much like the White Martians of Supergirl.
J'onn says that he had two daughters - K'hym and Tanya. In the comics, J'onn only had one daughter, though her name was also K'hym. In the Justice League animated series, J'onn had two children whose names and genders were never specified.
The White Martians used advanced technology, including something called fire-traps, to lay waste to the Green Martians.
J'onn can use a sample of White Martian's skin tissue to track it so long as it is in its own natural form.
(After Henshaw refuses to start digging through the DEO looking for a secret alien spy.)
Senator Crane: Fine. Let a mole run wild in here, just like you let a White Martian run wild in the street. But when you're brought down from the inside, remember this - you were warned.
(One Scene Later, as Senator Crane continues pushing)
Senator Crane: It's in your best interest to find this alien interloper as quickly as possible. Your entire operation's been compromised.
Henshaw: There are no hidden aliens here.
Senator Crane: Are you absolutely sure of that, Director Henshaw?
Henshaw: (regarding Senator Crane evenly) I wish I could say yes... but I never said you were attacked by a White Martian.
J'onn: We'd known war. But not like this. White Martians had been toiling underground, building weapons of death. Fire traps. Their technology overwhelmed us. There was no honor in how they fought. They herded us into camps. I swore no matter what I would protect my family. We wuld survive. But when we got through the gates... they took the women and children. Men were forced into labor. The others were sent to the furnace. My wife and daughters... burned! I escaped. I survived, to my great shame. I will hear my family's screams until the day I die.
Alex: Hank, you alright?
J'onn: I'm in the sewers, Danvers. Everything is just peachy.
J'onn: She's in the desert. You get Alex and get out.
Kara: I'm not leaving you alone with that thing.
J'onn: You have to. I'm done.
Kara: Done? Done with what? It has Alex. We have to stop it!
J'onn: This started because it wanted me dead. My race is gone. If I'm all that's left, let it have me.
Kara: No! This murderer does not get to win! And you don't get to give up!
J'onn: This will save lives.
Kara: We don't choose. We fight!
J'onn: Kara, I'm tired of being the last! Tired of having lived! You, of all people, know how heavy it is to survive.
Kara: I do. I ask myself every day why my mother didn't crawl into that pod with me. Now I know she felt guilty. She felt responsible for what happened on Krypton. Dying must have seemed... honorable. But dying's a lot easier than getting back up when the world's ended. You have to get up! You have to go on!
J'onn: My road is done. I'll help Alex and then join my people. Wherever they are.
Henshaw: (To Alex and Kara) My daughters were named K'hym and Tanya. It's not the same but... any man would be proud to call you his daughters.
Winn is actively avoiding Kara since the events of 110.
Lucy Lane is now working for Cat Grant.
Senator Miranda Crane is a good personal friend of General Sam Lane and shares his opinions on aliens... at least until the end of the episode, when her opinion changes due to Supergirl's efforts to save her.
White Martians are a subterranean species of Martian, who declared war on the surface-dwelling Green Martians, conquering them with their advanced technology. They killed all of the Green Martian race, save for J'onn J'onzz who was somehow able to escape and make his way to Earth.
The reason for J'onn's reluctance to use his powers is revealed when he explains that White Martians can sense his presence whenever he uses any of his powers except for shape-shifting, through a hive mind that all Martians share.
White Martians have the same powers as Green Martians, including shape-shifting, telepathy, phasing, flight, enhanced senses and enhanced physicality.
J'onn is 317 years old.
According to the captured White Martian, there are millions of their race still alive somewhere.
J'onn's daughters were named K'hym and Tanya.
Adam Foster asks Kara out on a date.
The episode ends with another Supergirl on the news, apparently throwing a wrecked vehicle off of a freeway.
The Fridge Factor
Between trying to force a reunion between Cat and her estranged son by lying, dropping the hunt for the White Martian to help Cat out after she makes the mistake of being herself with her estranged son and dating the son of the boss who is always one bad moment away from firing her forever... Kara does not come off as the brightest lure in the tackle-box in this episode.
She fairs slightly better than Alex, however, who seems to have been taken hostage by the bad guys in half of the episodes of the series so far.
The Bottom Line
There's two different stories in this episode. Neither of them really had anything to do with Supergirl and only one of them was worth telling. The subplot involving J'onn confronting one of the race that exterminated his own makes for an effective back-door pilot for a Martian Manhunter spin-off. Alas, most of the episode is focused on Cat Grant being a selfish, self-absorbed bitch and Kara trying to hide that fact from her son. I never thought I'd despair for an episode's lack of Winn but at least he would have been a distraction from pretending there's hidden depths or warmth to Cat Grant's character.