Supergirl: Can Lena Luthor Be Trusted?

SPOILERS AHEAD for tonight's episode of Supergirl.

Tonight's episode of Supergirl, titled "Crossfire," saw Lena Luthor playing a key role in saving the day...all while seemingly trying her best to prove that Kara and Supergirl were the same person.

Her suspicious behavior, along with some duplicitous (if seemingly well-meaning) actions in the episode, raised a question that fans have been asking since the season premiere: can Lena Luthor be trusted?

"I mean — can anyone ever trust a Luthor? I think that's going to be the looming question overall," series star Melissa Benoist admitted during a conversation with reporters on the set of Supergirl late last week. "Lena and Kara have this awesome relationship…but it's inevitable. I don't think Kara is ever going to be able to truly know if a Luthor is something she shouldn't be suspicious of. But there is a true friendship there, and a mutual respect."

As if to put a finer point on that very question, Lena herself points out in dialogue more than once that it seems improbable to have the sister of Lex Luthor and the cousin of Superman working together for a common good:

It likely wasn't lost on many viewers that this conversation -- and the actions surrounding it -- were taking place just as Lena's mother was revealed as the director of Cadmus.

Lena, of course, is currently playing a major role as a villain in Superwoman, published by DC Comics under its best-selling Rebirth banner. And, with Tess Mercer being a notable exception (sometimes), it's usually a pretty deadly mistake to underestimate a Luthor -- something even Mama Luthor in her anonymous role as Cadmus's director told her flunkies -- who ignored the advice and died for it.

Of course, the episode ends with Director Luthor coming to see her daughter, and a barely-concealed contempt for her mother on the part of Lena. Still, it isn't as though both of them don't know she's got super-hearing and the like. They could be staging any and every part of the whole ordeal for Supergirl's benefit.

So...what do you think, readers? Can we trust Lena Luthor?

Supergirl airs Monday nights at 8 p.m. ET/PT on The CW.