Girl of Steel October 9, 2017

After losing Mon-El, Kara decides to give up her human life and dedicate herself full-time to being Supergirl. Meanwhile, a new menace threatens National City, and real estate mogul Morgan Edge makes a bid to buy up CatCo. Also, Alex confesses a secret to Maggie, a citizen of National City has a mysterious connection to Kara, and Lena makes a bold move.

Triggers October 16, 2017

Supergirl faces Psi, a thief who can psychically induce her victims' worst fears. Meanwhile, James deals with having a new boss at CatCo, and Alex and Maggie continue making plans for their wedding.

Far from the Tree October 23, 2017

Supergirl goes with Hank to Mars in response to M'gann's telepathic request for help. Meanwhile, Maggie invites her estranged father Oscar to her and Alex's wedding shower that's sponsored by Eliza.

The Faithful October 30, 2017

Kara learns of a cult-like organization of people that she's rescued... who consider her a god. Meanwhile, Sam has difficulty balancing her career with her personal life.

Damage November 6, 2017

Morgan accuses Lena of poisoning the children of National City with the lead bomb she used to drive off the Daxamites. Kara and Sam work to clear their friend's name. Meanwhile, Maggie and Alex break up.

Midvale November 13, 2017

Kara takes Alex home to Midvale after Alex and Maggie break up. While Alex deals with the end of her relationship, she and Kara remember the first time that they bonded as sisters while solving the murder of a fellow high school student.

Wake Up November 20, 2017

The DEO rescues Mon-El from a spaceship buried in 12,000 years of rock, but Mon-El remains strangely silent about how he got there. Meanwhile, Hank takes M'yrnn to the park, and Sam goes to her mother Patricia for answers about her birth.

Crisis on Earth-X, Part 1 November 27, 2017

Rather than wallow in self-pity, Kara and Alex go to Barry Allen and Iris West's wedding... only to find the ceremony interrupted by Nazi soldiers and villains from Earth-X including a mysteriously strong superpowered female warrior.

Reign December 4, 2017

Supergirl learns that a mysterious Kryptonian symbol suddenly appearing around the city heralds the appearance of the World Killer, Reign. She's a Kryptonian whose powers exceed Supergirl's... and who is determined to bring judgment to a sinful world. The tension between Lena and Morgan Edge continues to build.

Legion of Super-Heroes January 15, 2018

Mon-El and Imra decide whether to help the DEO battle Reign. Meanwhile, another Legionnaire attempts to help Kara emerge from the coma that Reign put her into after their battle.

Fort Rozz January 22, 2018

Supergirl and Saturn Girl are forced to recruit two female metas to find a prisoner on Fort Rozz, which is orbiting a sun that emits radiation fatal to males. Meanwhile, Alex babysits Ruby while Sam goes on a work trip.

For Good January 29, 2018

Morgan believes that a recent attempt on his life was made by Lena. When Lena is poisoned, Kara steps in to find out who is responsible for the escalation in hosility. Meanwhile, Sam turns to Alex for help determining the cause of her blackouts.

Both Sides Now February 5, 2018

The DEO easily captures Julia Freeman, the second Worldkiller Purity's body. While Supergirl and Alex try to get through to her, Mon-El asks Hank for his help repairing the Legion Cruiser.

Schott Through the Heart April 16, 2018

After Winslow dies, his wife Mary comes to National City to attempt to reunite with Winn. However, a new murderous toymaker threatens Winn and Mary, Meanwhile, M'yrnn asks Alex to keep a secret from Hank, and Mon-El tries to find the right time to tell Supergirl something important about one of the Worldkillers.

In Search of Lost Time April 23, 2018

M'yrnn tries to redirect his mental processes and ends up infecting the DEO with a telepathic rage virus. Meanwhile, Lena tries to convince Sam that the latter transforms into Reign during her blackouts.

Of Two Minds April 30, 2018

The third Worldkiller, Pestilence, begins striking down the citizens of National City.... including Winn and Alex. Supergirl and Imra disagree on how to deal with Pestilence, and Lena continues trying to find a cure for Sam.

Trinity May 7, 2018

Supergirl discovers that she has a mental link to Sam and Julia, and takes Lena and Alex with her to rescue them. Meanwhile, James faces a tough decision when he must decide whether to investigate Lena or not after she kept Reign's existence a secret.

Shelter from the Storm May 14, 2018

Lena provides Alex with a safehouse to protect Ruby from Reign, who is looking to severe the last ties of humanity that Sam has with her family. Meanwhile, Supergirl discovers that Lena has been manufacturing Kryptonite, and the Legionnaires depart for the future.

The Fanatical May 21, 2018

Followers of Coville plan to use his journal to create a new Worldkiller. Meanwhile, Supergirl tries to repair the rift between her and Lena, and James is forced to consider whether to out himself or not.

Dark Side of the Moon May 28, 2018

Supergirl and Mon-El find a remnant of Krypton drifting deep in space. Meanwhile, Alex faces a killer from her past, and Winn ends up babysitting Ruby.

Not Kansas June 4, 2018

Kara and Mon-El return to Argo City, but not all is as it seems. Meanwhile, in Supergirl's absence, Guardian and the DEO deal with a dangerous gunman wielding DEO weaponry.

Make It Reign June 11, 2018

Supergirl and Mon-El try to get to Earth to stop the Daughters of Juru from resurrecting Reign and triggering Earth's destruction. Meanwhile, Hank participates in The Reach with his father, and Ruby demands the truth from Sam.

Battles Lost and Won June 18, 2018

The heroes must come up with a way to defeat Reign without killing her. Afterward, Winn and Alex get job offers, Mon-El and Hank make decisions about their personal lives, and James has a news story for the world.