When Supergirl returns for Season 5, all of National City's heroes will band together to take on a new threat, and The CW has released a new set of official stills from the premiere episode.

The stills from the episode entitled "Event Horizon" show Kara, in her new suit as Supergirl, joined by Brainiac 5, Dreamer, James Olsen's crimefighting alter ego Guardian, Alex Danvers and J'onn Jonzz in his civilian identity confronting an unseen enemy. Additional photos detail a conversation between James and his sister Kelly Olsen, who arrived in National City in Season 4 and began a burgeoning relationship with Alex.

RELATED: Supergirl's First Season 5 Teaser Showcases Kara, Lena and A New Villain

The network released the first set of official stills from the Season 5 premiere last month, teasing a confrontation at a theater, with the newest set expanding upon this as Brainiac is seen brandishing some sort of futuristic device.

Season 5 will also see a new villain in Midnight, who has been described as the living embodiment of darkness itself, escaping from an otherworldly prison. Given this origin, the heroes of National City may need to pull out all the stops to contain the new threat.

RELATED: Supergirl Season 5 Poster Gives New Look at Show's Key Players

Returning Sunday, Oct. 6 at 9 p.m. ET/PT on The CW, Supergirl stars Melissa Benoist as Kara Danvers, David Harewood as Martian Manhunter, Mehcad Brooks as Jimmy Olsen and Chyler Leigh as Alex Danvers.