'Supergirl': Lena Faces off With the DEO In "Trinity" Clip

The CW has released a scene from "Trinity", tonight's upcoming episode of Supergirl.

The episode will see Supergirl and the DEO deal with the major revelation at the end of last week's episode: that Reign is Sam Arias (Odette Annable) but perhaps even more damning that Lena Luthor (Katie McGrath) knew and didn't tell anyone. That revelation creates tension between Lena and Supergirl, as evidenced in the scene. You can check it out in the video above.

The fact that Lena didn't come to Supergirl and the DEO about Sam will lead to some challenges between the women, according to co-showrunner Jessica Queller. These challenges will be particularly difficult for Kara who, because Lena is unaware of her Supergirl identity, has a completely separate relationship than the Girl of Steel.

"One thing that we play a lot with in the upcoming episodes is the triangle between Lena, Kara, and Supergirl, because Lena has a very different relationship with Kara Danvers than she does with Supergirl," Queller told TV Line. "Something we had never played before that we are really examining and excited about in the upcoming episodes is that Lena and Supergirl are at odds about certain things and a bit angry with one another, but Lena and Kara are best friends. Lena feels the closest to Kara of anyone in the world, so then Kara is suddenly in this position where is sort of living two lives with one of her best friends. And although we've always had to see Supergirl maintain a dual identity, it's very personal when it comes to Lena, and it's very challenging for Kara, and so we're really interested in that dynamic."

If the complicated dynamic wasn't enough, a preview for "Trinity" hinted that Supergirl will have a more physical challenge as well. A solar eclipse -- whether it is naturally occurring or a machination of the Worldkillers is unclear -- may strip Supergirl of her powers, not a good situation especially as it appears the Girl of Steel will be facing off with the three, united Worldkillers on their home turf. According to the official synopsis for the episode, the showdown will have all of Team Supergirl bracing for an epic battle.

Supergirl airs Monday nights at 8/7c on The CW. "Trinity" debuts tonight, May 7.

Do you think Lena and Kara's friendship will survive the secrets of this season? Let us know your thoughts in the comments below.