Previously – Brainiac took over Superman’s body and, as Superbrainiac, brought the Kandor space station to Metropolis to give Earth the chance to be part of Krypton’s Empire. Lois Lane put on a Black Mercy device to retrieve Superman’s mind from Brainiac’s simulation. Jimmy and Kara carted Lois’ unconscious body around and found themselves fugitives on Earth. Steve Lombard rescued them from the clutches of Amanda Waller and the Human Defense Corps as Lois freed Superman from the Black Mercy. Superman regained his body, and Brainiac’s mind returned to his robot body on Kandor. Seeing Earth fight back, Brainiac decided to destroy the planet. He hijacked Lex Luthor’s kryptonite-powered Metallo robots and fought off every attack Earth sent against him. He even took down Superman and Kara.
Brainiac celebrates his victory over Earth’s forces by announcing that he gave the planet a chance but has now decided to purge it. The show skips over the title sequence and continues the action. Hank Henshaw leads a squadron of jets against Kandor while Amanda Waller fights the Metallos on the ground. Waller can’t contact Agent Wilson, but she does still have Lex. She orders him to shut the Metallos down, but he realizes that he can’t and simply runs away.
Steve drives his van with Lois and Jimmy inside, but they are attacked by Metallos. Fortunately, John Irons shows up in his Steel armor and destroys the robot. He tells them that the others are with Superman and Kara.
Superman finds himself barely able to move with the kryptonite all around. Kara is also out. Help arrives in the form of supervillains. Namely, Livewire, Heat Wave, Rough House, Silver Banshee, and Mist. Waller does her best with a simple handgun against the Metallos, but she needs Sam Lane to save her. It turns out Sam is the one coordinating Earth’s forces, and he hands Waller a bigger gun.
Superman reasons that taking down Brainiac is the key to saving the world. Kara uses her suit to bring up Kandor’s schematics. Steel and the super villains protect Superman and Kara from the kryptonite-powered robots as the Kryptonian heroes board Kandor. Brainiac laughs because he wanted them there.
Brainiac says “Eradicator Override”, another trigger word for Kara, and then he reveals 
the truth. Jor-El and other Kryptonians were losing the war and decided to negotiate peace. Brainiac was built for war, and he feared this would mean he would be decommissioned, so he decided to destroy Krypton.
This revelation was so intense Brainiac got to drop an “H” bomb when he said he cast Krypton into Hell. Him being responsible for the planet’s destruction makes perfect sense for what we’ve seen so far. Brainiac himself says it was 22 years ago, but we still don’t get further insight as to which alien race was so powerful that Krypton sought a ceasefire. Considering this is Brainiac’s biased POV, we could very well see a different side of Krypton when we get more of this story.
Once again under Brainiac’s influence, Supergirl attacks Superman. She is backed by Kandor’s robots. Superman takes the fight outside the space station and pulls off some flying maneuvers that lead the robots to take each other out. His fight with Kara brings them back to ground level, allowing Lois and Jimmy to arrive on the scene.
Kara goes on the offense, but Superman doesn’t fight her. He chooses to hug her instead and tells her that she is stronger than Brainiac. She can hear Brainiac’s voice and remembers him calling her weak and a failure. Lois and Jimmy join in on the hug to show their support and love for Kara. Kara breaks free of Brainiac’s control and unleashes some kind of super scream. The show’s theme song finally kicks in as Kara flies into the air and grabs Kandor. Superman joins her, and together they hurl Kandor into space.
Brainiac initiates the Black Zero Protocol, infecting Kandor and himself with kryptonite radiation. He realizes that he is about to die, and if the Kryptonian Empire is to end, Superman and Kara have to die too. He fires Kandor’s Archer Beam, this time with kryptonite energy, at them. Kara pushes Superman out of the way and takes the full force of the blast. She plummets into the sun.
Kara experiences a strange regression where she turns into a child. The child version of 
Kal-El flies towards her and reaches out. He saves her, and they both become adults again. Superman worries that they can’t escape the sun’s gravitational pull, but Kara realizes the power of the sun is making them stronger. They fly out of the sun, and Kara finally gets her Supergirl costume.
More powerful than ever, Superman and Supergirl fly through another Archer Beam straight to Kandor, which they demolish. Brainiac, with a kryptonite scythe arm, attacks. Supergirl breaks him in two and recovers a bit of Kandor technology. Brainiac falls into the sun. Earth cheers, and when Supergirl thinks they’re cheering for Superman, he points out they are cheering for both of them.
Kara wakes up in a bedroom in the Kents’ house in Smallville. Lois and Jimmy are asleep on the couch. Clark enters and tells Kara that she has been out for a few days. She also sports a scar on her face. Clark introduces her to Ma and Pa Kent. Clark takes her outside for the Kent family tradition of playing catch. Kara wants to win, but Clark points out it’s not a game you can win. He throws the ball so hard it hurts her hand. He isn’t holding back, and neither will she.
The end credits play over a montage of scenes while Clark, Jimmy, and Lois narrate. The Kents have a cookout in their backyard with a ton of the show’s supporting players. Clark’s voice over says it’s been a week since the invasion. Jimmy takes over the narration saying Superman and his cousin saved them. Jimmy and Kara work alongside Brain and Mallah and perform construction work. Lois narrates that everyone put aside their differences. Perry learns that Vicki Vale has scooped him again with an exclusive Supergirl interview. Clark explains that the invaders were defeated, but a glimpse of a news broadcast reveals that Amanda Waller is still at large. Lois says the invasion brought out the best and worst of people but that there will be new threats. A LexCorp building stands firmly in the middle of the city. Lex Luthor, along with Agent Wilson in a business suit, are pleased to see it.
There’s a post credit scene of Clark meeting Lois on the Daily Planet building. He is supportive of her moving to Gotham and has even looked up apartments with easy rooftop access. He tells her that no matter where she goes, all she has to do is say his name and he’ll be there. Lois admits that she turned down Vicki’s offer because she doesn’t want to be the second Vicki Vale. She wants to make her own name in Metropolis, and she wants to stay with the man she loves. Jimmy and Kara arrive with soup. The four of them enjoy their meal on the rooftop until Clark and Kara hear a call for help. They quickly change into Superman and Supergirl. Before they can leave, Lois points out that reporters should be on the scene. Superman takes Lois by the hand, Supergirl takes Jimmy by the hand, and the four of them fly off.
So that was our big season 2 finale. First and foremost, it concluded the story of Brainiac, 
who caused Krypton’s destruction so that he could continue conquering other planets. Kara realizes that Brainiac was never her father, and she was the one to deliver the final blow to him. The evilness of the Kryptonian empire died with Brainiac, but a brighter legacy of Krypton lives on in both Superman and Kara.
Kara finally gains a home planet and is free from the burden of carrying an entire empire, and Clark also gains something in finding his cousin. Clark has found someone he can be super around. A previous episode raised the question of whether or not the Kents stifled Clark by making him hold back his power. Now that he has Kara, Clark can relax knowing there is someone who can keep up with him. Even though Kara knows he thinks of himself as Clark, she does call him “Kal-El” at the end of the episode. This time, it feels more like Kara is encouraging Clark to embrace his Kryptonian heritage while accepting his Earth upbringing.
Clark and Kara’s story became the most important plot of the season, and the finale did wrap up Clark and Lois’ relationship woes, but other stories fell by the wayside. Namely, those involving Jimmy Olsen and Sam Lane. Jimmy and Kara clearly like each other, but there was no final admission of feelings. Jimmy also didn’t get the chance to reconcile with Clark. Their relationship wasn’t as damaged as the one between Clark and Lois, but Clark was clearly hurt by Jimmy ignoring his phone call. Clark and Jimmy didn’t get to spend any one on one time, which was a shame. Sam left Lois with no warning a few episodes ago, and although he did arrive with crucial help, Lois never got to confront him about abandoning her. He appears at the Kent cookout, so there was clearly downtime for Sam and Lois to talk, but we don’t see any of it.
The supervillains arriving to help was fun, but we could have seen some John Irons in the lead-up to it. The last we saw of him, Lex had stripped him of his armor. How much trouble did he have to go through to get it back? Speaking of Lex, him running from trouble isn’t out of character but partnering up with Agent Wilson is. There was no explanation as to why Wilson didn’t respond to Waller. He had been building up resentment towards her, but that was because she showed favoritism towards Lex. So why is Wilson with Lex now? What deal has been made?
Taking the Superman/Supergirl vs. Brainiac fight into space was epic and all, but it had some logic issues. It has been established that Kryptonians can survive in space, but they shouldn’t be able to talk to each other or Brainiac without any communication device. The trip to the sun should have taken much longer than what was shown unless everyone was moving faster than the speed of light. Even the people on Earth were somehow aware of the result of the space fight because they were able to cheer Superman and Supergirl’s victory.
A few Easter Eggs and hints popped up throughout the episode. Brainiac name drops “Eradicator” to turn Kara into a killing machine. In the comics, the Eradicator was a device whose over protection of Krypton puts it at odds with Superman. Brainiac’s characterization on this show is very Eradicator-like. Superman’s blue bio-energy appears when the sun powers him up. Something similar happens to Kara, but her energy is red. This is reminiscent of the Superman Red/Superman Blue energy beings from the 90’s comics. It isn’t explained how, but the trip to the sun also enabled Kara to transform her Kryptonian space suit into a suit like Clark’s. The scar Kara got from fighting Brainiac remained a week later when she woke up in Smallville, but it seems to have healed by the final scene.
Perry White’s article about the invasion is titled “My Adventures with Superman”. We don’t get Kara being named or choosing the name Supergirl, but thanks to Vicki Vale’s article, we know that’s what the public will be calling her. So with the episode being named “My Adventures with Supergirl”, a new Kryptonian hero joins the My Adventures with Superman family.
Overall, this was a strong finale to a strong season. There will be a season 3, and that hopefully will pick up some of the neglected plot threads and continue to take Superman and his friends to new places.
