VIDEO : 'Supergirl' Presents New Challenge For Kara and Lena

'Supergirl' last left off with Lena Luthor learning her employee Sam was the Worldkiller, Reign.

But some other secrets may cause friction with Lena and Kara.

The show's co-showrunner Jessica Queller said it sets up a triangle between the friends that makes it "challenging" for Kara and her super identity.

Lena has a very different relationship with Kara Danvers than she does with Supergirl... Lena and Supergirl are at odds about certain things and a bit angry with one another, but Lena and Kara are best friends... And although we've always had to see Supergirl maintain a dual identity, it's very personal when it comes to Lena.
Jessica Queller

'Supergirl' airs Mondays at 7 pm Central on The CW.