Series overview
Season 123456
"Never give in. Never, in nothing, great or small, large or petty, except in considerations of honor and good sense. Never yield to force, or the apparently overwhelming might of the enemy that confronts you. Never. Never, ever, give in."
Ben Lockwood[src]

Supergirl​​​​ was renewed for a fourth season by The CW on April 2, 2018. It premiered on October 14, 2018, and concluded on May 19, 2019. The season consisted of 22 episodes.


Main cast

Recurring cast


# Episode name Directed by Story by Teleplay by Original airdate
1 "American Alien" Jesse Warn Robert Rovner & Jessica Queller Gabriel Llanas & Aadrita Mukerji October 14, 2018
Diving back into reporting, Kara welcomes a new cub reporter to CatCo. Meanwhile, James and Lena argue about James' impending indictment for acting as the vigilante Guardian, while Alex and Brainy struggle to get in sync at the D.E.O.. Supergirl is called into action when remnants of the anti-alien terrorist organization Cadmus try to assassinate pro-alien leaders, but their endgame turns out to be much more sinister than she expected. J'onn relishes his peaceful new life, but an outing with an old friend causes him concern.
2 "Fallout" Harry Jierjian Dana Horgan Maria Maggenti & Daniel Beaty October 21, 2018
A shocking revelation causes chaos in National City. Supergirl sets out to capture Mercy Graves, while Alex takes control at the D.E.O.. Back at CatCo, Kara decides to write an investigative story on Mercy and asks Lena if she can interview her as Mercy has ties to the Luthors. Meanwhile, Brainy meets Nia and the two end up in a precarious situation.
3 "Man of Steel" Jesse Warn Rob Wright & Derek Simon October 28, 2018
Ben Lockwood didn't always hate aliens. Through a series of incidents, and input from his anti-alien father, Ben slowly transforms from a mild-mannered professor into the villainous Agent Liberty of today.
4 "Ahimsa" Armen Kevorkian Eric Carrasco Katie Rose Rogers & Jess Kardos November 4, 2018
When Supergirl needs help, Alex asks Lena and Brainiac to team up; J'onn questions his decision to quit the D.E.O., but after running into Manchester Black, he realizes there are a lot of ways to help his fellow aliens.
5 "Parasite Lost" David McWhirter Maria Maggenti & Aadrita Mukerji November 11, 2018
Colonel Haley makes a surprising decision regarding Supergirl. Kara writes a series of articles highlighting aliens in National City in the hopes that humans will stop being so fearful of them. Unfortunately, the article puts some of the aliens in harm's way.
6 "Call to Action" Antonio Negret Gabriel Llanas & Daniel Beaty November 18, 2018
Everyone gathers for Thanksgiving but Kara is feeling down after her televised debate with Ben Lockwood about the anti-alien sentiment coursing through National City. Meanwhile, James and Lena argue about the best way to handle the Children of Liberty.
7 "Rather the Fallen Angel" Chad Lowe Dana Horgan & Katie Rose Rogers November 25, 2018
James falls in deeper with the Children of Liberty in his efforts to meet Agent Liberty. Meanwhile, Supergirl and Manchester Black follow a lead on Agent Liberty's location, but things take a dark turn. Lena kicks off her first set of trials.
8 "Bunker Hill" Kevin Smith Rob Wright & Eric Carrasco December 2, 2018
Nia has a powerful dream about Agent Liberty but refuses to look at it as a prophetic dream and pushes it aside. After noticing something is bothering Nia, Kara enlists Brainy's help, and the two try to persuade Nia to embrace her destiny. Meanwhile, Manchester Black pays Ben Lockwood a menacing visit.
9 "Elseworlds, Part 3" Jesse Warn Marc Guggenheim Derek Simon & Robert Rovner December 11, 2018
Supergirl, the Flash, Green Arrow and Superman engage in the battle of their lives.
10 "Suspicious Minds" Rachel Talalay Maria Maggenti & Gabriel Llanas January 20, 2019
Colonel Haley is upset after Supergirl responds to a distress call from a Navy ship that turned out to be a deadly alien attack. Colonel Haley reclaims the site as DEO territory and demands that Supergirl step aside. After Supergirl refuses to be told what to do, Haley refocuses her energy on finding out Supergirl's true identity and begins to interrogate all DEO agents, including Alex. Meanwhile, Brainiac-5 tries to persuade Nia to embrace her superpowers but she misinterprets his motives.
11 "Blood Memory" Shannon Kohli Jessica Queller & Dana Horgan January 27, 2019
Kara joins Nia on a trip to Nia's hometown to visit her family during the town's annual Harvest Festival. While home, Nia's mother (guest star Kate Burton) encourages her daughter to embrace her destiny. Meanwhile, Alex deals with a street drug that is turning people violent and giving them temporary superpowers.
12 "Menagerie" Stefan Pleszczynski Robert Rovner Daniel Beaty & Greg Baldwin February 17, 2019
With his P.I. shingle newly hung outside his office, J'onn welcomes new clients. Trying to take her mind off what happened at the D.E.O., Kara decides to team up with J'onn on his latest assignment, which unfortunately ends up tying directly into Alex's current investigation that involves the villain Menagerie (guest star Jessica Meraz). Meanwhile, Lena shares some news with James, but his reaction isn't what she expected. Nia invites Brainy to her Valentine's Day party.
13 "What's So Funny About Truth, Justice, and the American Way?" Alexis Ostrander Eric Carrasco & Aadrita Mukerji March 3, 2019
Manchester Black breaks out of prison with the help of his new team, the Elite, who are set on punishing the anti-alien forces. Supergirl pulls double duty as she tries to apprehend Manchester Black and his team as well as deal with a shocking new development with Ben Lockwood.
14 "Stand and Deliver" Andi Armaganian Rob Wright & Jess Kardos March 10, 2019
Between Ben Lockwood's new push to stir up the anti-alien movement and the Elite's desire to target Lockwood and his minions, Supergirl is concerned about the safety of the American people – both human and alien. When Lockwood organizes a rally, the aliens decide to peacefully protest. Brainiac and J’onn join the alien march while Supergirl and Dreamer patrol to keep everyone safe. Meanwhile, James picks up his camera again to cover the march for CatCo, and Hayley assigns Alex a job that clashes with her beliefs. When the Elite and Ben Lockwood stir up trouble at the rally, Supergirl is forced to take a stand.
15 "O Brother, Where Art Thou?" Tawnia McKiernan Derek Simon & Nicki Holcomb March 17, 2019
Secretly furloughed from prison due to failing health, Lex Luthor visits his sister, Lena, to seek her help finding a cure. Savvy as ever, Lena is suspicious of Lex's motives but when she's faced with a life and death situation, she must decide how she truly feels about her brother. Meanwhile, Supergirl and J'onn face off against Manchester Black. James’ sister Kelly comes to town.
16 "The House of L" Carl Seaton Dana Horgan & Eric Carrasco March 24, 2019
In the wake of Lex Luthor's return, the show flashes back to what he's been doing for the last two years and how his secret machinations and plans have affected Supergirl and Lena.
17 "All About Eve" Ben Bray Gabriel Llanas Katie Rose Rogers & Brooke Pohl March 31, 2019
Supergirl must deal with the destructive aftermath of Lex’s nefarious plans. Shocked at what Lex has created, Supergirl faces her biggest challenge yet.
18 "Crime and Punishment" Antonio Negret Rob Wright Lindsay Sturman & Aadrita Mukerji April 21, 2019
Kara and Lena head to Stryker's Island to search for clues on how to defeat Lex. At the prison, Kara tries to befriend a nosy prisoner, Steve, who may have insight into what Lex was doing, while Lena studies an array of puzzles Lex left behind in the hopes of discovering his whereabouts. While there, a prison riot breaks out and Kara must find a way to stop the prisoners without revealing her secret identity as Supergirl. Meanwhile, Kelly encourages James to talk to someone for his PTSD, and Alex faces off against Ben Lockwood after he storms the D.E.O. and acquires some powerful weapons to hunt Supergirl.
19 "American Dreamer" David Harewood Dana Horgan Daniel Beaty & Jess Kardos April 28, 2019
As Kara doggedly works as a reporter to clear Supergirl's name, Dreamer picks up the slack as National City’s protector, which leads to a showdown with Ben Lockwood. James takes drastic measures to relieve his PTSD.
20 "Will The Real Miss Tessmacher Please Stand Up?" Shannon Kohli Derek Simon Katie Rose Rogers & Natalie Abrams May 5, 2019
Kara and Lena head to Kaznia to hunt down Lex. However, Eve Teschmacher sets a trap for the duo that could ultimately reveal that Kara is Supergirl. Meanwhile, Alex gets a long-awaited phone call, James practices using his powers, and Ben Lockwood takes a dangerous stand inside the D.E.O..
21 "Red Dawn" Alexis Ostrander Lindsay Sturman Gabriel Llanas & Eric Carrasco May 12, 2019
Kara comes face-to-face with Red Daughter and the two engage in an epic battle. Determined to find a way to extract the Harun-El, Lena turns to an unlikely source for help – Lillian Luthor. Meanwhile, Alex realizes she's missing parts of her memory, & Brainy, Nia & J’onn set out to track down aliens who've been abducted by Lex.
22 "The Quest for Peace" Jesse Warn Robert Rovner & Jessica Queller Rob Wright & Derek Simon May 19, 2019
Lex Luthor descends upon Washington, D.C. and summons Lena and Lillian Luthor to the White House. Supergirl realizes she has one last chance to stop Lex and turns to the power of the press to help her.


Title cards

End title cards

Promotional images


  • This season airs on Sundays at 8/7c, as opposed to the past three seasons that aired on Mondays at 8/7c.
  • Manchester Black was originally going to be the main antagonist of this season.[1]
  • Jeremy Jordan was supposed to appear as a recurring role this season, but unfortunately, was unable. He will appear in the fifth season.[2]


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