'Supergirl': Lena Visits the DEO in "Trinity" Photos

The CW has released photos for "Trinity", the upcoming episode of Supergirl set to air on May 7.

Supergirl's (Melissa Benoist) battle to stop the Worldkillers has reached a critical point going into "Trinity". Pestilence made her debut and, along with Purity, rescued Reign/Samantha Arias (Odette Annable) from where she was being kept in Lena Luthor's (Katie McGrath) lab. With all three Worldkillers teamed up, things are all that more dire for not just National City but the world as well. And from the looks of the photos taking on the three Worldkillers will require everyone on Team Supergirl -- and Lena as well.

You can check out the photos in the gallery below.

Supergirl 03x17 Gallery

In addition to the photos, we know from a preview for "Trinity" that Supergirl will also have an uphill battle because of her powers as well. An 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 trio in their Fortress. The photos reveal that Mon-El (Chris Wood), Imra/Saturn Girl (Amy Jackson), and Alex (Chyler Leigh) are there as well.

Lena's appearance in the photos also may hint at some tension between Lena and Supergirl. Series co-show runner Jessica Queller recently told TV Line that there will be some challenges develop because Lena didn't come to Supergirl about Reign.

"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," co-show runner Jessica 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."

But it's not just Reign that could create issues between Kara and Lena. There have been previous times when Lena's work has come into conflict with Supergirl. Now, it sounds like keeping Reign a secret will lead to a difficult confrontation between the two women who, in any other circumstance, are close friends.

"In an upcoming episode, there's a big reveal that Lena has something in her lab that will enrage Supergirl and the DEO, and it turns into an epic battle of wills between the two women, Lena and Supergirl," Queller said. "I wouldn't want to miss it."

Supergirl airs Mondays at 8/7c on The CW.