Kara became a mean lady hero in "Supergirl" season 1 episode 16. Also, episode 17 is set to see J'onn J'onzz talk about some information about Kara and Alex's father.

On Mar. 15, "Supergirl" tweeted a promo clip for the series' upcoming episode. As per the video, Kara is set to act strange, in a negative way. Further scenes in the video saw the superhero in battle with the police, causing explosions, as well as throwing someone from the roof top.

"Supergirl" season 1 episode 16 is entitled "Falling." According to The Inquisitr, Maxwell Lord and Lord Industries developed a synthetic kryptonite as their means to keep Non from going back to Earth and annihilate the whole planet. Rumors say that the kryptonite was not same with the original, since it glows red and not green.

As per the publication, the synthetic kryptonite was responsible on Kara's strange and evil behavior, which eventually turned Kara as the "Mean Girl" counterpart of Supergirl. In line with this, Lord developed a tool to permanently eradicate the presence of the "Red K" from the superhero; however, it would not take effect immediately.

According to Spoilers Guide, the episode saw Kara turn on her friends, as well as the citizens of National City, after her exposure to the red kryptonite. Episode 16 also saw Hank Henshaw take on his Martian Manhunter form to save Alex. He got locked in the alien cell at the DEO.

In "Supergirl" season 1 episode 17, J'onzz is set to reveal the details of meeting Kara and Alex's father, Dr. Jeremiah Danvers, along with expressing Henshaw's identity. Kara is also set to argue about entrusting Siobhan and someone new with her alter ego.

"Supergirl" season 1 episode 16, "Falling," aired on Mar. 14 while episode 17, "Manhunter" is set to air on Mar. 21.