Watch Supergirl Season 4 full episodes online, free and paid options via our partners and affiliates.

Lillian and Lena Are Summoned - Supergirl
Watch Supergirl Season 4 Episode 22
"The Quest for Peace"
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On Supergirl Season 4 Episode 22, Supergirl realizes she has one last chance to stop Lex as she turns to the power of the press to help her.

An Unlikely Source - Supergirl
Watch Supergirl Season 4 Episode 21
"Red Dawn"
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On Supergirl Season 4 Episode 21, Kara comes face to face with Red Daughter and the two engage in an epic battle, and Lena turns to Lillian Luthor for help.

Tessmacher Sets a Trap - Supergirl
Watch Supergirl Season 4 Episode 20
"Will The Real Miss Tessmacher Please Stand Up?"
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On Supergirl Season 4 Episode 20, when Kara and Lena try to hunt down Lex, Eve Tessmacher sets a trap that could ultimately reveal that Kara is Supergirl.

Drastic Measures - Supergirl
Watch Supergirl Season 4 Episode 19
"American Dreamer"
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On Supergirl Season 4 Episode 19, Kara doggedly works as a reporter to clear Supergirl's name as Dreamer picks up the slack as National City's protector.

Lena Looks For Clues - Supergirl
Watch Supergirl Season 4 Episode 18
"Crime and Punishment"
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On Supergirl Season 4 Episode 18, Kara and Lena head to Stryker's Island to find clues to defeat Lex, while Lena studies an array of puzzles Lex left behind.

The Aftermath - Supergirl
Watch Supergirl Season 4 Episode 17
"All About Eve"
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On Supergirl Season 4 Episode 17, Supergirl faces her biggest challenge yet as she must deal with the destructive aftermath of Lex's nefarious plans.

Lex Luthor's Next Plan - Supergirl
Watch Supergirl Season 4 Episode 16
"The House of L"
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On Supergirl Season 4 Episode 16, Lex Luthor reveals all about his daring plan to rid the world of Supergirl, but how far will he go to win the battle?

Kara and Alex Hug It Out - Supergirl
Watch Supergirl Season 4 Episode 15
"O Brother, Where Art Thou?"
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On Supergirl Season 4 Episode 15, Lex Luthor gets a furlough from prison due to ill health, but what is the villain's master plan to take down a hero?

Worried For Everyone's Safety - Supergirl
Watch Supergirl Season 4 Episode 14
"Stand and Deliver"
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On Supergirl Season 4 Episode 14, with Ben Lockwood's push to stir up the anti-alien movement, Supergirl is worried about the safety of both humans and aliens.

Catching Manchester Black - Supergirl
Watch Supergirl Season 4 Episode 13
"What's so Funny About Truth, Justice, and the American Way?"
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On Supergirl Season 4 Episode 13, Supergirl pulls double duty as she tries to apprehend Manchester Black and his team and deal with a shocking new development.

Looking For a Distraction - Supergirl
Watch Supergirl Season 4 Episode 12
"Menagerie"
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On Supergirl Season 4 Episode 12, Kara decides to team up with J'onn on his latest P.I. assignment but it ends up tying directly into Alex's current situation.

Embrace Her Destiny - Supergirl
Watch Supergirl Season 4 Episode 11
"Blood Memory"
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On Supergirl Season 4 Episode 11, Nia is encouraged to embrace her destiny and Alex deals with a drug that turns people violent and gives them superpowers.

Colonel Haley - Supergirl
Watch Supergirl Season 4 Episode 10
"Suspicious Minds"
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On Supergirl Season 4 Episode 10, Colonel Haley and Supergirl clash when she handles a distress call from a Navy ship that turns out to be an alien attack.

Cheers! - Supergirl
Watch Supergirl Season 4 Episode 9
"Elseworlds, Part Three"
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On Supergirl Season 4 Episode 9, the Elseworlds crossover continues, and Cisco continues to cause problems for his former friends. Can anyone get through to him?

Persuading Nia - Supergirl
Watch Supergirl Season 4 Episode 8
"Bunker Hill"
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On Supergirl Season 4 Episode 8, Kara and Brainy try to persuade Nia to embrace her destiny after she has a powerful dream about Agent Liberty.

Following a Lead - Supergirl
Watch Supergirl Season 4 Episode 7
"Rather the Fallen Angel"
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On Supergirl Season 4 Episode 7, Supergirl and Manchester Black track down a lead on Agent Liberty's location when things end up taking a dark turn.

Alex Danvers - Supergirl
Watch Supergirl Season 4 Episode 6
"Call to Action"
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On Supergirl Season 4 Episode 6, the characters meet up for Thanksgiving, but Kara is struggling after her conversation with Ben Lockwood on national tV.

Kara's Article - Supergirl
Watch Supergirl Season 4 Episode 5
"Parasite Lost"
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On Supergirl Season 4 Episode 5, Kara writes s series of articles highlighting aliens in National City but inadvertently ends up putting them in harm's way.

Rethinking His Decision - Supergirl
Watch Supergirl Season 4 Episode 4
"Ahimsa"
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On Supergirl Season 4 Episode 4, Alex asks Lena and Brainiac to team up to help Supergirl while J'onn questions his decision to quit the DEO.

The Turning of Ben Lockwood - Supergirl
Watch Supergirl Season 4 Episode 3
"Man of Steel"
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On Supergirl Season 4 Episode 3, Ben transforms from a mild-mannered professor into the villainous Agent Liberty with input from his anti-alien father.

On a Mission - Supergirl
Watch Supergirl Season 4 Episode 2
"Fallout"
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On Supergirl Season 4 Episode 2, a shocking revelation causes chaos in National City and Supergirl heads off in an attempt to capture Mercy Graves.

Called Into Action - Supergirl
Watch Supergirl Season 4 Episode 1
"American Alien"
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On Supergirl Season 4 Episode 1 Alex and Brainy try to get in sync, James faces an indictment for the vigilante Guardian, and Supergirl is called into action.

Supergirl Season 4 Quotes

Lex Luthor: As another world leader once said, "I don't see why men shouldn't be as cruel as nature."
Lillian Luthor: Try not to quote Hitler in public, dear. It'll hurt the brand.

I just finally feel like the world is good. And I so badly want it to stay that way even if it's just for a little while.

Kara