And they've partnered with Warner Bros. Interactive for the release. Unfortunately there's currently no media barring a press release around the game, but given the success of Left 4 Dead and the learnings they will have taken from the Evolve debacle, Back 4 Blood is likely on the right path.

And so as to that press release:

Next-gen Co-operative FPS from Zombie Video game Visionaries to Propel Beloved Genre Forward

BURBANK, CA – March 14, 2019 – Warner Bros. Interactive Entertainment and Turtle Rock Studios today announced Back 4 Blood, from the creators and development team behind the critically acclaimed, co-op phenomenon Left 4 Dead. Back 4 Blood is designed from the ground-up as an original, premium title and marries the best of what made the co-op zombie shooter so successful with new features and state-of-the-art technology.

“We are thrilled to partner with the proven Turtle Rock Studios team on Back 4 Blood to advance the co-op zombie genre forward with innovative multiplayer gameplay,” said David Haddad, President, Warner Bros. Interactive Entertainment. “The talented team at Turtle Rock has been developing amazing games together for a long time, and this is a great opportunity to work with them to create a new gaming universe built specifically with the large co-op zombie shooter community in mind.”

“It’s hard to overstate what an awesome opportunity this is. We get to return to a genre that was born in our studio with over ten years of additional experience and zombie ideas racked up in our brains,” said Chris Ashton, Co-founder and Design Director, Turtle Rock Studios. “We also have some of the best teammates in the business at WBIE who understand our development process and are equally committed to our player-first mentality. We love being able to announce, so we can start working with the community right away.”

“We are not resting on any past laurels. Our goal is to take all we’ve learned and push forward. We know that’s a tall order,” said Phil Robb, Co-founder and Creative Director, Turtle Rock Studios. “We’re growing the team considerably because we’re stepping up to the biggest challenge in this studio’s history. We know this title has to stand out and we fully intend to make that happen.”

You can read a basic FAQ on the freshly-announced game right here. Hopefully we see something moving from a media point of view at this year's E3.