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Supergirl Season 4 Episodes

22 Episodes 2018 - 2019

Season 4 of the drama series opens with Kara (Melissa Benoist) going back to her reporting job at CatCo while still working with the DEO, proving that she can both be a superhero and have a normal life. Meanwhile, an attempt on President Marsdin's (Lynda Carter) life exposes her as an alien, causing chaos in National City; Mercy (Rhona Mitra) and Otis (Robert Baker), the siblings responsible for the crime, manage to escape and become a threat to the DEO. With humans becoming more and more anti-alien, Kara and her friends try their best at showing that aliens and people with superpowers aren't dangerous but can be exceptional allies against forces of evil.

Episode 1

American Alien

Sun, Oct 14, 2018 60 mins

In the Season 4 premiere, 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 DEO. 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.

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Supergirl, Season 4 Episode 1 image

Episode 2


Sun, Oct 21, 2018 60 mins

A shocking revelation causes chaos in National City. Supergirl sets out to capture Mercy Graves, while Alex takes control at the DEO. 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.

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Supergirl, Season 4 Episode 2 image

Episode 3

Man of Steel

Sun, Oct 28, 2018 60 mins

Ben Lockwood did not always hate aliens. Ben slowly transforms from a mild-mannered professor into the villainous Agent Liberty of today through a series of events and input from his anti-alien father.

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Supergirl, Season 4 Episode 3 image

Episode 4


Sun, Nov 4, 2018 60 mins

When Supergirl needs help, Alex asks Lena and Brainiac to team up. Meanwhile, J'onn questions his decision to quit the DEO. However, after running into Manchester Black he realizes there are a lot of ways to help his fellow aliens during this tumultuous time.

Where to Watch
Supergirl, Season 4 Episode 4 image

Episode 5

Parasite Lost

Sat, Nov 10, 2018 60 mins

Colonel Haley makes a surprising decision regarding Supergirl. Kara writes s 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.

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Supergirl, Season 4 Episode 5 image

Episode 6

Call to Action

Sun, Nov 18, 2018 60 mins

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.

Where to Watch
Supergirl, Season 4 Episode 6 image

Episode 7

Rather the Fallen Angel

Sun, Nov 25, 2018 60 mins

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.

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Supergirl, Season 4 Episode 7 image

Episode 8

Bunker Hill

Sun, Dec 2, 2018 60 mins

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.

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Supergirl, Season 4 Episode 8 image

Episode 9

Elseworlds, Part 3

Tue, Dec 11, 2018 60 mins

Supergirl, the Flash, Green Arrow and Superman engage in the battle of their lives.

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Supergirl, Season 4 Episode 9 image

Episode 10

Suspicious Minds

Sun, Jan 20, 2019 60 mins

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.

Where to Watch
Supergirl, Season 4 Episode 10 image

Episode 11

Blood Memory

Sun, Jan 27, 2019 60 mins

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 encourages her daughter to embrace her destiny. Meanwhile, Alex deals with a street drug that is turning people violent and giving them temporary superpowers.

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Supergirl, Season 4 Episode 11 image

Episode 12


Sun, Feb 17, 2019 60 mins

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 DEO, 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. Meanwhile, Lena shares some news with James, but his reaction isn't what she expected.

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Supergirl, Season 4 Episode 12 image

Episode 13

What's so Funny About Truth, Justice, and the American Way?

Sun, Mar 3, 2019 60 mins

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.

Where to Watch
Supergirl, Season 4 Episode 13 image

Episode 14

Stand and Deliver

Sun, Mar 10, 2019 60 mins

Supergirl is concerned about the safety of the American people, both human and alien, due to Ben Lockwood's push to stir up the anti-alien movement and the Elite's desire to target Lockwood and his minions. When Lockwood organizes a rally, the aliens decide to peacefully protest. Brainiac and J'onn join the march while Supergirl and Dreamer patrol to keep everyone safe. Meanwhile, James picks up his camera to cover the march for CatCo, and Hayley assigns Alex a job that clashes with her beliefs.

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Episode 15

O Brother, Where Art Thou?

Sun, Mar 17, 2019 60 mins

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.

Where to Watch
Supergirl, Season 4 Episode 15 image

Episode 16

The House of L

Sun, Mar 24, 2019 60 mins

In the wake of Lex Luthor's return: A flashback to what he's been doing for the last two years and how his secret machinations and plans have affected Supergirl and Lena.

Where to Watch
Supergirl, Season 4 Episode 16 image

Episode 17

All About Eve

Sun, Mar 31, 2019 60 mins

Supergirl must deal with the destructive aftermath of Lex's nefarious plans. Shocked at what Lex has created, Supergirl faces her biggest challenge yet.

Where to Watch
Supergirl, Season 4 Episode 17 image

Episode 18

Crime and Punishment

Sun, Apr 21, 2019 60 mins

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.

Where to Watch
Supergirl, Season 4 Episode 18 image

Episode 19

American Dreamer

Sun, Apr 28, 2019 60 mins

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.

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Episode 20

Will The Real Miss Tessmacher Please Stand Up?

Sun, May 5, 2019 60 mins

Kara and Lena head to Kaznia to hunt down Lex. However, Eve Tessmacher 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 DEO.

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Episode 21

Red Dawn

Sun, May 12, 2019 60 mins

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, and Brainy, Nia and J'onn set out to track down aliens who have been abducted by Lex.

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Episode 22

The Quest for Peace

Sun, May 19, 2019 60 mins

In the Season 4 finale, 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.

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Supergirl, Season 4 Episode 22 image