'Supergirl' Discovers Part of Krypton in "Dark Side of the Moon" Promo

On Supergirl, Kara has lived with the knowledge that Krypton was destroyed and her family killed in the process. However, in a promo for next week's "Dark Side of the Moon" Supergirl discovers that may not be the case.

In tonight's episode, Supergirl and her allies discover that it may be possible to reverse-engineer the Worldkiller creation process, but it requires a specific Kryptonian stone in order to do so. When the only stone of its type is rendered inert, Winn (Jeremy Jordan) and Lena (Katie McGrath) discover the same stone on an asteroid roughly five light years away. However, as you can see in the video above, Supergirl (Melissa Benoist) and Mon-El (Chris Wood) discover there's far more to that asteroid than a rock. Part of Krypton survived the planet's destruction and that's not all.

In the preview Kara discovers what appears to be her mother, Alura Zor-El (Erica Durance), alive and well on this remnant of Krypton. The idea of Kara's mother still being alive is something that we've speculated about before. In an interview last summer, co-showrunner Robert Rovner hinted that Alura would have significance during the show's third season.

"We wanted to keep Alura's presence on the show because it really connects Kara to Krypton and her roots and what it meant to see her family and her planet destroyed," Rovner said. "It's an emotional grounding that's always important."

At the time, Rovner said that Kara's tie to Alura and to Krypton would have a heavy hand in the season's themes, though at the time it was framed as part of a larger question about what it means to be human. However, if Alura -- and other members of Kara's family and culture -- survived the demise of Krypton -- it's a revelation that could change everything for Supergirl.

It could also have major impact on Team Supergirl's attempts to figure out how to defeat Reign and save Sam (Odette Annable) in the process. Time is running out as Reign has begun to adapt to the Kryptonite used to subdue her and is growing increasingly more violent and more powerful. Aside from perhaps providing the stone needed to save Sam, this discovery of a portion of Krypton might just provide Supergirl with help should Reign get the upper hand again.

Supergirl airs on Monday nights at 8/7c on The CW. "Dark Side of the Moon" will debut on May 28.