The pic will be a co-production between Netflix and Skydance, who will help with financing.
Several suitors had lined up to distribute and co-finance the movie, including Bay's home studio Paramount, but in the end, Netflix won out after it committed to Bay's budget of around $125 million, making it one of the streamer's biggest productions ever -- behind Martin Scorsese's mob epic "The Irishman" and on par with David Ayer's "Bright."
The deal is another milestone for Netflix and film chief Scott Stuberas the studio continues to draw major talent. Netflix has been drawing more and more actors like Will Smith and Brad Pitt, but Bay is one of the first big-name directors to bring a big-budget tentpole to the studio.
For the Reynolds, the movie marks another possible franchise to add to his resume, with "Deadpool 2" off to a powerful start at the box office. The other element that made "Six Underground" appealing to Reynolds, besides working with Bay for the first time, is that a Netflix film does not include the world press commitments that a major studio movie like "Deadpool" requires, and will give him the chance to immediately jump back into developing the next "Deadpool" and "X-Force" pic for Fox.
The film will also reunite him with "Deadpool" and "Deadpool 2" scribes Paul Wernick and Rhett Reese, who wrote the spec.
The actioner is based on an original idea from Wernick and Reese, who will also executive produce. Skydance's David Ellison, Dana Goldberg, and Don Granger will produce "Six Underground" along with Bay.
Variety first reported in March that Bay was planning "Six Underground" and the Amblin pic "Robopocalypse" as his next two films. Bay still plans to shoot this and "Robopocalypse" back to back, with the latter going into production in 2019. "Six Underground" is targeting a summer start of production for a worldwide release in 2019 on Netflix.