Kara saved the day using the power of writing, just as she'd intended at the beginning of the season. Hat is revealed to be an alien whose Bowler hat has fifth-dimension properties. While it was initially announced that he would shift into a recurring capacity for the fourth season, Rovner later said he would not appear until the fifth season. She takes on a volunteer, Adam, who dies during the trial, after bonding with Lena through their shared motivational grief. Lex escapes with Otis, but is stopped by Supergirl.
Supergirl reveals her concerns about people like Lex gaining powers and her not being able to stop them. Colonel Haley dismisses Kara from the crime scene because of her continued refusal to reveal her identity. They confirmed that the fourth season would look to refocus on Kara's professional career as a reporter and see her act as a mentor to 's former protégé, both at CatCo and as a superhero, paralleling Kara's own journey of coming into her own. Manchester has Children of Liberty member Petrocelli held captive to torture him for information. She initially gains the upper hand, but her weakened state causes her to fall during the fight. The duplicate Kara is seen punching through walls in an underground cavern surrounded by Kasnian soldiers.
Nia has a powerful dream about Agent Liberty but refuses to look at it as a prophetic dream and pushes it aside. Ben returns to his duties as Agent Liberty. That kind of wound is undoubtedly going to fester over the summer hiatus, and I'm afraid that Lena may become the show's next villain as she leads in her brother's footsteps and makes good on the Luthor name. Supergirl is making a statement this season with the first few episodes focusing on anti-alien protests and the people who are committing hate crimes against aliens. Brainy realizes Ben will come for the alien registry next, so he downloads a copy of it before deleting the original. After noticing something is bothering Nia, Kara enlists Brainy's help, and the two try to persuade Nia to embrace her destiny. During the episode, another supporting character talks about being introduced to Ahimsa and how it helped him.
Brent Spiner had been announced as Vice President Baker, but he was replaced by Bruce Boxleitner. Later, Supergirl, Nia, Brainy, Alex, and J'onn stop The Elite, while Supergirl learns that the Claymore satellite has been reprogrammed to destroy The White House. His priorities have been all sorts of screwed up from day one, and they cost him his wife, his family and his freedom. Meanwhile, J'onn and Kara continue investigating Manchester, who confronts the two by using the Martian Staff of Kolar, which triggers J'onn's traumatic memories. Sadly, Lena has already accepted the negative version of Kara's decision to withhold the truth. What do you predict for the upcoming season? Since then, the Kaznians have been training the Supergirl copy while Lex raised and manipulated her for his own uses, teaching her a biased history about her rival, the original Supergirl.
President Baker declares against Supergirl, who is now public enemy number one, though Alex, Lena and Haley all believe she is innocent. Marsdin resigns, leaving Vice President Baker to replace her. And when Lena attempts to calm him down, his frustration turns to anger, causing him to lash out at her for not being able to help even more. However, after running into Manchester Black guest star David Ajala , he realizes there are a lot of ways to help his fellow aliens during this tumultuous time. Lex frames it in a way to make Lena feel that all of her friends have been laughing at her and she truly has no one. At the same time, Nia asks James not to don his Guardian persona again as it might be too dangerous. And although things got a little dicey for a bit, Brainy and Lena managed to purify the air in enough time for Kara to apprehend Otis and Mercy Graves.
And the only thing more surprising than his tearful display is the cause of his uncharacteristic outburst. Her heart, however, makes her weaker then Kryptonite ever could. His son realizes his best friend is an alien, having kept this a secret because of Ben's policies, which makes him reconsider his parents' anti-alien propaganda. After narrowly escaping Deegan, Barry and Oliver locate , who works as a mob boss with James as a henchman, and retrieve Superman from Earth-38. Kara recovers her evidence from Brainy and publicly exposes Lex.
The fact that Lena attended the victory game night and played it cool is worrisome. In a series of flashbacks, , a university professor, and his family suffer a series of personal tragedies that slowly turn him against aliens and lead him into the path of Mercy Graves, who gives him the Agent Liberty armor. James points out that heroes do something even when facing danger. They find her cousin Bitsie, whom they learn was given the cure to eradicate her cancer; persuaded to help, Bitsie reveals the location of Eve's old lab. At L-Corp, Mercy and Lena fight, each using an arm piece of Lex's exoskeleton.
Has Supergirl just set up its next villain? Though his sister Kelly tries to stop her, Alex convinces Kelly to stop. J'onn completes his mission on Mars. Hilariously enough, Lockwood was most upset about Luthor taking his Secretary of Alien Affairs gig, a gig he didn't earn on his own merit, might I add. While attending the press conference, James is left unable to move out of fear, so he turns to his sister for therapy. Now deputized, he and the Children of Liberty begin arresting innocent aliens. Kara, whose powers are only partially drained, manages to attract his attention with her heat vision.