Jessica Parker Kennedy will not only appear on The Flash when the series airs its upcoming 150th episode, currently in production, but will actually suit up as the superhero XS. It's arguably not surprising -- her character was confirmed for more than just the one episode, and it feels unlikely that you bring somebody back for multiple episodes without breaking out their old super-suit -- but given that the currently-in-production episode will also see the return of Jay Garrick (John Wesley Shipp) and an appearance by Bart Allen (Jordan Fisher), the episode will mark a pretty epic, multigenerational speedster team-up, which alone would be enough to excite fans of The Flash.
Nora West-Allen/XS was first introduced during the "Crisis on Earth-X" crossover event, in which she was just a mysterious young woman who shared a few words with Barry Allen at his wedding rehearsal dinner. She later re-emerged a few times before revealing herself as Barry and Iris West-Allen's daughter from the future. Revealing she had traveled back in time in order to prevent Barry's disappearance in "Crisis on Infinite Earths," Nora was ultimately wiped from reality after helping to defeat Cicada.
The revelation that Nora will suit up again came from an Instagram story in which Kennedy filmed her legs and feet -- in purple and yellow -- making their way to an on-set trailer that said "XS."
SOCORRO! É ELAAA! ⚡🗣️🗣️
A Jessica Parker Kennedy, intérprete da Nora West-Allen postou stories e podemos ver parte do traje da XS e o camarim.
🗞️ @TheFlashBRAMay 6, 2021
Nora spent all of season five documenting things in her journal using a special time language that does not change no matter what happens to the timeline. That proved useful when that journal helped Team Flash build an artificial speed force -- something that turned out ot be necessary, since the original one was destroyed -- even after the writer of the journal itself had been erased from existence. There have been frequent references to Nora since her death, including her costume appearing in a kind of museum exhibit that Team Flash put together to honor their fallen allies.
"With comic book characters, anything could happen," Kennedy said back in 2019. "She's gone for now, but I think that there's always a way to bring somebody back, on a show like that, and I definitely would be happy to do something like that. But yeah, as far as I know, she's gone, for the moment."