Season Four Episode Guide

Supergirl (401) - American Alien

American Alien

Episode #: 401
Air Date: 10.14.18
Our Rating:

A brother-sister team with ties to the Luthors attack an alien scientist, prompting John to suspect a new, anti-alien movement in National City. Kara helps a new cub reporter at Catco, and Lena worries about James' impending indictment for vigilantism.
Supergirl (402) - Fallout

Fallout

Episode #: 402
Air Date: 10.21.18
Our Rating:

As the country is rocked by a shocking revelation about the President, Mercy Graves targets the alien masking technology inside L-Corp. After Brainy and Nia feel the sting of anti-alien bias first-hand, Nia turns to James Olsen to intervene.
Supergirl (403) - Man of Steel

Man of Steel

Episode #: 403
Air Date: 10.28.18
Our Rating:

Ben Lockwood faces a rapidly-changing world when the government welcomes off-world aliens as American citizens, which he perceives to be a threat to his family and the family steel business -- slowly transforming from a mild-mannered professor into the villainous Agent Liberty.
Supergirl (404) - Ahimsa

Ahimsa

Episode #: 404
Air Date: 11.04.18
Our Rating:

J'onn teams up with a man named Manchester Black to search for Fiona, ending up on the trail of the anti-alien movement. Supergirl struggles with her new reality inside a protective suit, and Brainy struggles with his emotions.
Supergirl (405) - Parasite Lost

Parasite Lost

Episode #: 405
Air Date: 11.11.18
Our Rating:

As Alex prepares for Colonel Haley's new role at the D.E.O., Liberty recruits his own Parasite to use against National City's alien population. Kara writes a profile of a legendary alien healer, and is surprised by the negative backlash from the anti-alien community.
Supergirl (406) - Call to Action

Call to Action

Episode #: 406
Air Date: 11.18.18
Our Rating:

James tries to get loser to the Children of Liberty, while Manchester Black conducts an interrogation. Lena and Miss Tessmacher experiment to try and unlock the powers of the Harun-El, and Colonel Haley flexes her authority at the D.E.O.
Supergirl (407) - Rather the Fallen Angel

Rather the Fallen Angel

Episode #: 407
Air Date: 11.25.18
Our Rating:

James gets a face-to-face meeting with Agent Liberty, who intends to use James for propaganda. Meanwhile, Lena begins morally dubious human trials in what she hopes will give regular people super powers.
Supergirl (408) - Bunker Hill

Bunker Hill

Episode #: 408
Air Date: 12.02.18
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Manchester Black confronts Ben Lockwood in his home, placing Lockwood's wife in danger. When Nia has a powerful and distressing dream, Brainy and Kara help her to embrace her secret abilities to track down Agent Liberty.
Supergirl (409) - Elseworlds, Part 3

Elseworlds, Part 3

Episode #: 409
Air Date: 12.11.18
Our Rating:

After Dr. Deegan takes another shot at rewriting reality Oliver and Barry find themselves on the run from the law, with Kara locked up inside Star Labs -- and a dark Superman reigning supreme.
Supergirl (410) - Suspicious Minds

Suspicious Minds

Episode #: 410
Air Date: 01.20.19
Our Rating:

Colonel Haley sets her sights on learning Supergirl's secret identity, forcing Alex to run interference with her own agents. Meanwhile Supergirl searches for a shimmering alien after an attack at sea.
Supergirl (411) - Blood Memory

Blood Memory

Episode #: 411
Air Date: 01.27.19
Our Rating:

Kara joins Nia on a trip to her hometown, where a disturbing dream about her mother brings a bad omen -- and complicates Nia's relationship with her sister. Alex chases a street drug that is turning users into raging monsters, and James faces a difficult choice when a reporter brings him a story about Lena's company.
Supergirl (412) - Menagerie

Menagerie

Episode #: 412
Air Date: 02.17.19

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. (The CW)
Supergirl (413) - What's So Funny About Truth, Justice, and the American Way?

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

Episode #: 413
Air Date: 03.03.19

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. (The CW)
Supergirl (414) - Stand and Deliver

Stand and Deliver

Episode #: 414
Air Date: 03.10.19

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. Meanwhile, James picks up his camera again to cover the march for CatCo, and Hayley assigns Alex a job that clashes with her beliefs. (The CW)
Supergirl (415) - O Brother, Where Art Thou?

O Brother, Where Art Thou?

Episode #: 415
Air Date: 03.17.19

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. (The CW)

The House of L

Episode #: 416
Air Date: 03.24.19

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. (The CW)