Season 4 (Supergirl)

Season 4
Information
Network	The CW
Start Date	October 14, 2018
End Date	May 19, 2019
Time Slot	Sundays at 8:00 pm Tuesdays at 8:00 pm (4x09)
Number of Episodes	22
Chronology
Preceded by	Season 3
Followed by	Season 5

The fourth season of Supergirl premiered on October 14, 2018, and concluded on May 19, 2019. The season consists of 22 episodes.

Synopsis

Season Three saw Supergirl stop Reign and the other Worldkillers' threat to humanity and our planet, and in the process, Kara was shocked to find her mother Alura alive and living in a salvaged Argo City that survived the destruction of Krypton. Reconnecting with her past caused Kara to realize that her true home is now here on Earth, where big changes are taking place for her and all of her friends in National City – and also, it appears, for a doppelganger in Russia! With a wave of anti-alien sentiment roiling the country led by Agent Liberty; and a new command at the DEO, Colonel Haley – Kara returns to CatCo, where she mentors young reporter Nia Nal, who evolves into a superhero herself. Season four promises to be full of surprises, action, adventure and lots of big revelations for Supergirl, Alex, James, J'onn, Lena, and Brainiac-5.

Cast

Main Cast

• Melissa Benoist as Supergirl (Kara Danvers) / Red Daughter
• Mehcad Brooks as Guardian (James Olsen) / Jimmy Olsen
• Chyler Leigh as Alex Danvers / Alex Danvers
• Katie McGrath as Lena Luthor
• Jesse Rath as Brainiac-5/Barney Fife (Querl Dox)
• Sam Witwer as Agent Liberty (Ben Lockwood)
• Nicole Maines as Dreamer (Nia Nal)
• April Parker Jones as Lauren Haley
• David Harewood as Martian Manhunter (J'onn J'onzz)

Recurring Cast

• Lynda Carter as Olivia Marsdin
• Jon Cryer as Lex Luthor
• Brenda Strong as Lillian Luthor
• Rhona Mitra as Mercy Graves
• Robert Baker as Metallo (Otis Graves)
• Tiya Sircar as Fiona Byrne
• Anthony Konechny as Parasite (Raymond Jensen)
• Jaymee Mak as Mackenzie
• Bruce Boxleitner as Phil Baker
• Andrea Brooks as Eve Tessmacher
• Sarah Smyth as Lydia Lockwood
• Graham Verchere as George Lockwood
• David Ajala as Manchester Black
• Donna Benedicto as Agent Reiff
• Steve Byers as Tom
• Roxy Wood as Yvette Turner
• Jessica Meraz as Menagerie (Pamela Ferrer)
• Louis Ozawa Changchien as Hat
• Azie Tesfai as Kelly Olsen
• Françoise Robertson as Sarah Walker

Episodes

#	Episode Title	Directed by	Story By	Teleplay By	Episode 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 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. J'onn relishes his peaceful new life, but an outing with an old friend causes him concern.
2	Fallout (Supergirl)	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 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.
3	Man of Steel (Supergirl)	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 V. Kevorkian	Eric Carrasco	Katie Rose Rogers & Jess Kardos	November 4, 2018
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.
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 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 Downer	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 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. 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 (Supergirl)	Ben Bray	Gabrial Llanas	Katie Rose Rogers & Brooke Phol	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	April 21, 2019
Supergirl and Lena head to Stryker's Island to search for clues on how to defeat Lex. At the prison, Supergirl tries to befriend a nosy prisoner, Steve, who may have insight into what Lex was doing, but he and all of the prisoners regard her as a traitor to the country and refuse to talk to her. Lena realizes Lex left behind clues for her and deciphering them could be the key to his whereabouts. Meanwhile, Kelly encourages James to talk to someone about his PTSD, and Alex faces off against Ben Lockwood after he storms the DEO and acquires some powerful weapons to hunt Supergirl.
19	American Dreamer	David Harewood	Dana Horgan	Daniel Beaty & Jess Kardos	April 28, 2019
As Kara (Melissa 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.
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 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.
21	Red Dawn	Alexis Ostrander	Lindsay Sturman	Gabrial 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, and Brainy, Nia and J'onn set out to track down aliens who have 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, DC 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.

Soundtrack

On June 4, 2021, an album consisting of incidental music from the season was released digitally on Spotify and Amazon Music.

Gallery

Logos and Title Cards

• 
  Official Title Card
• 
  Variant Title Card for Elseworlds, Part 3
• 
  Variant Title Card for The House of L, Red Dawn, & The Quest for Peace
• 
  Official Logo

Promotional Images

• 
  "A Force Against Fear"
• 
  Key Art
• 
  First look at Nicole Maines as Dreamer
• 
  First look at Jon Cryer as Lex Luthor