In the upcoming season of the hit superhero show "Supergirl" from The CW, it appears National City may be under a new threat that could prove to be a major setback to Kara Danvers a.k.a. Supergirl (Melissa Benoist).

New images for season 3 were just released recently which revealed the residents of National City at a ceremony somewhere downtown but looking very worried. Kara and J'onn J'onzz a.k.a. Martian Manhunter (David Harewood) appear to be looking up at something with a concerned demeanor while people around them scamper to safety.

In another picture, Alex Danvers (Chyler Leigh) and her partner Maggie Sawyer (Floriana Lima) look worried on a viewing deck when they see something from afar. It remains to be seen who this seemingly powerful threat is and how Supergirl will contain this mysterious villain.

Also revealed in a couple of images another new villain named Reign (Odette Annabel) who is also called "Worldkiller." However, in these pictures, she appears to be just like any other ordinary human. In one image, she is crouched on her knee while in another picture she is embracing a younger female while looking on worriedly at something.

This strongly suggests that Reign may not have her powers yet but may seemingly follow a story arc throughout the season. At the end of which, she may become the powerful "Worldkiller" she is supposed to be.

In related news, Bollywood actress Amy Jackson was just cast as Saturn Girl a.k.a. Imra Ardeen in the upcoming season. She is described as a smart and strong-willed hero who also has telekinetic abilities. She was born on Titan, one of Saturn's moons, and will be a valuable ally to Supergirl as they battle together against threats toward National City.

"Supergirl" season 3 will return on Monday, Oct. 9 at 8 p.m. EDT on the CW.