Things are not looking bright for the beloved characters of The CW's post-apocalyptic series "The 100" when the show returns for its fourth season early next year.

According to a report from Variety.com, series creator Jason Rothenberg recently hinted that the Earth will be more and more of an adversary for the characters of "The 100" in its upcoming season, posing a threat to their very survival.

"The earth strikes back in Season 4, it is an unbeatable foe," Rothenberg shared. "It quickly becomes about not how to stop it, because stopping it is not possible, but how do we survive? There aren't enough lifeboats, so who gets to choose who lives?"

The series creator even went as far as sharing an unfinished shot from the next season, which showed the Grounder city of Polis being overshadowed by a dark cloud of radioactive fallout, solidifying fans' beliefs that Season 4 of "The 100" will indeed focus on a nuclear crisis.

In the teaser shot presented by Rothenberg at Comic-con, one of the voices of the main characters, Clarke Griffin, can be heard narrating something about survival: "Our enemy isn't something that can be fought, it can't be reasoned with, it can't be killed. When all is lost, can hope survive? Can we survive? After everything we've done, do we deserve to?"

In a separate article on TV Line, the actress who plays Griffin, Eliza Taylor, was quoted as saying that her character will act as a unifying force against the nuclear crisis in Season 4 of "The 100." She also stressed the theme of survival in the upcoming episodes of the post-apocalyptic show.

"It's going to be interesting to watch a group of people, humans, trying to survive," Taylor said. "This is an enemy we can't defeat, so how do we move forward? In true Clarke fashion, that will be trying to get everyone on board."