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"Maybe that's the lesson of high school. You're not meant to suppress the bad emotions, you're simply meant to endure them. So you can appreciate the good ones when they come."
Brainy to Nia[src]

"Prom Again!" is the sixth episode of the sixth season of Supergirl, and the one-hundred-twelfth episode overall. It aired on May 4, 2021.



The episode picks up where "Prom Night!" left off, with Nia and Brainy trapped by the aliens. However, Kara hears them in distress and goes to their aid. In the scuffle, Nia and Brainy get free and manage to stop the aliens. However, Cat's been watching and recording the whole thing via drone.

With Brainy and Nia free, they claim they are ready to leave and Kenny and Kara have to get ready for prom. Brainy later tells Nia that he set the aliens on course to Uruguay so they can reset space time. However, Nia then has a dream of the cage and the cat again, but Brainy thinks it must just be a dream echo.

Cat, determined to find her story, starts throwing rocks out in the clearing until she uncovers the ships and starts pressing buttons until she releases the aliens. They take her onto her ship and lock her up in one of their cells.

Alex drives Kara to prom and the sisters have a heartfelt chat in the car. Alex tells her she's proud of her and apologizes for how she's behaved lately. She now realizes that Kara can handle anything. She also tells Kara that because she has to wear a mask every day, she should take the night off and not wear a mask to the prom. Alex then goes to photograph the meteor shower.

On the time ship, Nia and Brainy share a dance before prom.

At the school, the meteor shower starts, interrupting Kara from talking to Kenny. She takes off to stop the meteor from hitting the school, something that Alex witnesses. The meteor is made of kryptonite, though, and Kara falls from the sky and lands in the gym, alive but weakened by kryptonite. As they're sorting things out, the aliens broadcast a message demanding that the aliens reveal themselves or else. Kenny claims to be the Kryptonian and the aliens take him before vanishing.

The aliens figure out that Kenny is human and that he sacrificed himself for his friend so now they plan to use him as bait and throw him in a cell with Cat. Naxim sends a message to the aliens and says that the Kryptonian has 10 minutes to turn themselves over or they will kill Kenny. Nia and Brainy subdue Kara and then take off themselves to go find Kenny.

Alex takes the Kryptonite shards out of Kara's hand and after talking -- with Alex warning her that she will never get to be normal again if she gets caught -- Alex, picks the lock to the janitor's closet they're stuck in so that Kara can get into natural light. A recharged Kara takes off. Nia has another dream, this time, she holds off the cougar so that she can try to read the cage for details, discerning the letters P. W. She loses control of things and comes out of the dream, but brings the cougar with her, sending it chasing the aliens, a power Brainy calls lucid dreaming. When they get on the ship, they realize that the cougar from Nia's dreams is actually about Cat.

Kara shows up at the ship and in a scuffle they end up releasing all the aliens that have been captive on board. Cat escapes, and the police show up just as Naxim and his sidekick escape. Brainy and Nia watch in horror as Kara is confronted by Cat and the cops, realizing that the timeline has been altered and it can't be undone. Nia says they can use the time ship to go back in time to fix it, going back just a few hours so they can stop Cat. Kara overhears and breaks out of police custody and flies off.

Nia and Brainy go back in time a few hours and prepare to change things, but quickly discover that they aren't alone. Kara has stowed away with them. She tells them that she realizes that she doesn't want her future to be tangled up with cops and reporters so she wants to change things back. With time of the essence, they agree to let her help, but they accidentally come in contact with Alex and Kenny. Nia finds Cat's drone and shoots it down and then comes face to face with Cat. Nia ends up giving Cat a peptalk, telling her she's a visionary and even sets her on the path to calling herself Cat rather than CJ. With that out of the way, the timeline resets itself.

An inspired Cat quits her job at The Daily Planet and begins to draft her plans for CatCo -- with the logo inspired by the cougar from Nia's dream. Naxim's ship sends a surrender beacon to the DEO and flies off. The meteor shower happens and again, Kara responds. She's downed by the Kryptonite and while waiting for Alex to get the car to take her home, Kara and Kenny have a serious conversation about their future, with Kara telling him she's going to National City University. Brainy and Nia get the rock with Kara's blood and head home.



Guest starring[]






  • While Kara Danvers and Kenny Li are exchanging corsages, the song "Bulletproof" by La Roux is playing. This song was released on June 21, 2009, but the events of this episode took place almost a month earlier on May 26.
    • However, since the timeline of Earth-Prime is different from real life (or was changed from Earth-38), it's entirely possible that it was released earlier.
  • Despite having Kryptonite in her arm for a prolonged period, Kara doesn't experience the same debilitating pain shown in multiple previous episodes.
    • This is especially noticeable since she doesn't recognize Kryptonite, so she could not have built up some tolerance (which she claimed to have done in Season 4).