The 100 is about to dive into an "environmental disaster story" in season four. Here's everything you need to know...

The 100 season four is almost upon us. We're keeping this hub updated with all of the latest news about the upcoming season.
We've got a new, ominous poster for The 100 Season 4. Things do not look good for any of the characters currently hanging out on planet Earth. Then again, "From the ashes, we will rise," is a pretty optimistic tagline for The 100. Maybe we'll make it to The 100 Season 5 after all...

There's also a new The 100 Season 4 trailer and, despite all of the blood, misery, and hints that the world is officially ending, it is somehow more upbeat than the last one. We credit the soundtrack (K.Flay's "Blood in the Cut") and Jasper and Monty's high five. Check it out...
Here's everything else we know about the upcoming season...
The 100 Season 4 Release Date
We've got a release date for The 100 season four! And it is... Wednesday, February 1st at 9 p.m., following Arrow.
The 100 Season 4 Trailers
The stakes are higher than ever in The 100 season four. Check out the trailer for yourself...
The 100 Season 4 - Trailer [HD] by denofgeek
For a full analysis of the above trailer, check out our trailer breakdown. And if the above trailer isn't enough to tide you over until season 4, check out this season three sizzle reel and season four "teaser" at SDCC...
The 100 Season 4 Premiere
Check out the latest The 100 season 4 photo sneak peeks (via Entertainment Weekly) in the above gallery, including one of Clarke and Bellamy looking serious together and one of new Grounder character Ilian (Chai Romruen). Speaking about Ilian, The 100 showrunner Jason Rothenberg teased: "He was forced to do some horrible things while being driven by A.L.I.E. He’s dedicated to making sure that never happens again."
Speaking more generally about the major themes of The 100 season 4, Rothenberg said:
If you can’t stop the end of the world, how can you find hope? Some people will cling to their loved ones, some people will fight to their last breath, and some people are just done fighting ... It’s human nature to save our families, our friends first. Can you take a little bit less for yourself in order to let somebody else have something?
The 100 Season 4 Cast
The remaining (as in: not yet killed of) cast is all returning, including: Eliza Taylor (Clarke), Bob Morley (Bellamy), Devon Bostick (Jasper), Christopher Larkin (Monty), Isiah Washington (Jaha), Henry Ian Cusick (Kane), Paige Turco (Abby), Marie Avgeropoulos (Octavia), Lindsey Morgan (Raven), and Richard Harmon (Murphy).
In addition to the returning main cast, Zach McGowan (Roan) has been upgraded to a series regular, which means we should see more from Roan in season 4.
Other cast members expected to return and/or appear include Sachin Sahel (Jackson), Adina Porter (Indra), Chai Romruen (Ilan), Nadia Hilker (Luna), Luisa D'Oliveira (Emori), Tasya Teles (Echo), Jarod Joseph (Miller), Chelsey Reist (Harper McIntyre), Chris Shields (David Miller), Jonathan Whitesell (Bryan), Jessica Harmon (Niylah), Jana Mitsoula (Willa), Joseph John Coleman (Taggart), Alex Pangburn (Hayes), and Jessica Williams (Kenza).
Yeah, The 100 has a big cast.
Jason Rothenberg teased at SDCC that we will meet a new character in the season four premiere's cold open, one of "a couple new characters that I think people will love." Could the cold open character in question be Chai Romruen's new recurring role? Deadline reported that the actor will be playing Ilan, "a Grounder haunted by the horrors he committed under ALIE's control."
The 100 writers room and cast have shared some behind-the-scenes shots of the cast and crew hard at work in the Vancouver wilderness...