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Supergirl Season 3 Episodes
Season 3 Episode Guide
23 Episodes 2017 - 2018
Episode 1
Girl of Steel
Mon, Oct 9, 201742 mins
Kara deals with the loss of Mon-El by focusing all her energy on being Supergirl and the mysterious new threat against National City. Alex confesses a secret to Maggie about their impending nuptials. A citizen of National City has a mysterious connection to Kara, and Lena makes a bold move.
Episode 2
Triggers
Mon, Oct 16, 201742 mins
Psi, a thief with psychic powers, attacks National City. Able to immobilize people by tapping into their worst fears, Psi proves a formidable opponent for Supergirl. Meanwhile, James and Lena are at an impasse, and Samantha starts her new job at L-Corp.
Episode 3
Far from the Tree
Mon, Oct 23, 201742 mins
Maggie reaches out to her estranged father when Eliza throws her and Alex a wedding shower, while Supergirl joins J'onn on a personal mission.
Episode 4
The Faithful
Mon, Oct 30, 201742 mins
Kara investigates a secretive new group whose leader, Thomas Coville, has a mysterious connection to Supergirl. Meanwhile, Samantha feels like she's letting Ruby down.
Episode 5
Damage
Mon, Nov 6, 201742 mins
When multiple children get sick from lead poisoning, Morgan Edge points the finger at Lena and blames her creation of the lead bomb she made to save National City from the Daxamites. While Lena knows she never intended any harm, she fears there may have been a flaw in her design, leaving her responsible. Kara teams up with Samantha to clear Lena's name, but it turns out to be harder than they thought. Meanwhile, Alex and Maggie make a crucial decision about the future of their relationship.
Episode 6
Midvale
Mon, Nov 13, 201742 mins
Kara and Alex head home to Midvale for a little R&R. While there, Kara recalls a painful memory of a childhood friend's death and how that traumatic experience brought the Danvers sisters closer together.
Episode 7
Wake Up
Mon, Nov 20, 201742 mins
Kara investigates when an alien ship lands deep underwater beneath National City; Hank attempts to bond with his father; Samantha looks to her estranged mother for answers.
Episode 8
Crisis on Earth-X, Part 1
Mon, Nov 27, 201742 mins
Barry and Iris's wedding brings the gang together, but things go awry when villains from Earth-X attack the ceremony. All of the superheroes band together with help from their super friends like Citizen Cold, The Ray, Felicity Smoak, Iris West and Alex Danvers to take on their most formidable villains yet. Earth's mightiest heroes - Green Arrow, Supergirl, The Flash and White Canary - lead their teams into battle to save the world.
Episode 9
Reign
Mon, Dec 4, 201742 mins
Supergirl investigates a mysterious symbol popping up all over National City, tracing its origins back to an ancient prophecy and the mark of the World Killer, Reign. Meanwhile, the tension between Lena and Morgan Edge continues to build, causing James to step in and offer up some protection, and possibly igniting a spark in the process.
Episode 10
Legion of Super-Heroes
Mon, Jan 15, 201842 mins
The battle with Reign has put Supergirl into a coma like state to try and heal. Brainiac-5 enters into Supergirls coma-dream and tries to explain to her that she has sustained so much injuries that her body is healed . While she is fine physically in a Legion Healing tube, its up to Supergirl to wake up or she will remain in a coma and die. The DEO has tried to subdue Reign but are having trouble without Supergirl. Will Mon El help the team? What is the secret that he is protecting? Why is Thomas Coville now helping Reign?
Episode 11
Fort Rozz
Mon, Jan 22, 201842 mins
As Reign continues to terrorise the city, Supergirl teams up with Saturn Girl, and the two recruit Supergirl's former enemies, Livewire and Psi, to form a team for a mission to Fort Rozz to recover a prisoner who has information on how to defeat Reign once and for all. Meanwhile, Alex babysits Ruby.
Episode 12
For Good
Mon, Jan 29, 201842 mins
Someone tries to kill Morgan Edge and he barely survives. He accuses Lena of being behind the attempt and vows to destroy her. When Lena fears her hatred for Morgan will take her to the Luthor dark side, Kara steps in to help her friend. Meanwhile, after Sam realizes she's losing time, she confides in Alex who decides to run some medical tests to see if she can find out what's going on with her new friend.
Episode 13
Both Sides Now
Mon, Feb 5, 201842 mins
The DEO captures another Worldkiller, who escapes and attacks the city's subway tunnels.
Episode 14
Schott Through the Heart
Mon, Apr 16, 201842 mins
Following the death of his father, Winn must work with his estranged mother to stop a copycat Toyman.
Episode 15
In Search of Lost Time
Mon, Apr 23, 201842 mins
Supergirl must work with J'onn to contain the chaos resulting from Myr'nn's psychic disturbances at the DEO; Mon-El teaches Kara fighting techniques he learned in the future for battling Worldkillers.
Episode 16
Of Two Minds
Mon, Apr 30, 201842 mins
Supergirl and Imra have different ideas on how to stop the third Worldkiller, Pestilence. However, when both Alex and Winn are seriously injured by Pestilence, Supergirl and Imra team up to stop the destruction.
Episode 17
Trinity
Mon, May 7, 201842 mins
Still reeling after learning about Lena's secret, Supergirl asks Guardian for a favor that could alter his relationship with Lena forever. Meanwhile, with all three Worldkillers united, Supergirl and the team brace for an epic battle.
Episode 18
Shelter from the Storm
Mon, May 14, 201842 mins
With Pestilence dead, Imra, Brainy and Mon-El plan to head back to the future. Reign surprises Lena and James at her apartment demanding to know where Ruby is. Lena sprays her with kryptonite to send he away. J'onn and Kara go to Sam's mom to learn all they can about her younger days. Sam's mom Patricia says she know that Sam is Reign. She drew her symbol on everything. Her mom kicked her out of the house. Meanwhile, Alex goes to see Ruby who is hidden in Lex's mansion. It is both invisible and has a communications shield. Reign shows up at her mom's hose looking for Ruby. What she sees a figure hiding in an upstairs closet is Supergirl, waiting with an electrical band weapon. In the fight that follows, Patricia is mortally wounded and J'onn and Supergirl realize Reign has all three Worldkiller powers. Brainy tells Mon-El that if one of them stays behind, the chances of beating Reign rise from 51% to 88.8%. As the trio near the disruption point for jumping into the future, Imra tells Mon-El to go back and help Supergirl. Lena brings Kara a case of super-charged kryptonite to use against Reign. Kara is not very gracious, but takes it. Ruby thinks Alex is lying to her about her mom and goes outside to phone her. Reign homes in on the signal. Mon-El says he can use Lena's kryptonite against Reign. At the mansion, Alex, Supergirl and Mon-El take on Reign eventually besting her with kryptonite bullets. Ruby sees that Reign is her mother.
Episode 19
The Fanatical
Mon, May 21, 201842 mins
When Tanya, a disciple of Coville's, escapes from what's left of his cult, she gives Kara and James a journal that could hold the key to saving Sam. Someone learns Guardian's identity and threatens to expose James if he doesn't do what they ask. James contemplates what it means to be a black vigilante without a mask in America.
Episode 20
Dark Side of the Moon
Mon, May 28, 201841 mins
Supergirl is stunned to discover that a part of Krypton survived. Meanwhile, Alex is attacked while out with Ruby, and Lena considers how far will she go to keep Reign contained.
Episode 21
Not Kansas
Mon, Jun 4, 201842 mins
Kara makes a major life decision. Meanwhile, J'onn finds out that special DEO-caliber guns have hit the streets of National City.
Episode 22
Make It Reign
Mon, Jun 11, 201842 mins
Supergirl learns the true depth of Selena's nefarious plans for Earth. Supergirl, Mon-El and Alura must devise a plan to stop her before Selena gets to Earth. J'onn prepares to say goodbye to his father.
Episode 23
Battles Lost and Won
Mon, Jun 18, 201842 mins
Supergirl and her team take on Selena in an epic battle for Earth.
