According to a report from Deadline, Warner Bros are "aggressively" moving forward with plans to make a Green Lantern Corps movie. To that end, they've reportedly hired Man of Steel writer David Goyer and Justin Rhodes to write the script. The movie, according to the report, will be an origin story and also a buddy cop movie, and will focus on Hal Jordan and John Stewart. Deadline isn't sure whether the studio will attempt to get Ryan Reynolds involved again, but that didn't go so well last time. They referred to the film as "Lethal Weapon in space."
As evidenced by his work on Man of Steel, Goyer is known for having tremendous respect for comic book characters and their fans, once saying on a podcast:
I have a theory about She-Hulk. Which was created by a man, right? And at the time in particular I think 95% of comic book readers were men and certainly almost all of the comic book writers were men. So the Hulk was this classic male power fantasy. It's like, most of the people reading comic books were these people like me who were just these little kids getting the s*** kicked out of them every day… And so then they created She-Hulk, right? Who was still smart… I think She-Hulk is the chick that you could f*** if you were Hulk, you know what I'm saying? … She-Hulk was the extension of the male power fantasy. So it's like if I'm going to be this geek who becomes the Hulk then let's create a giant green porn star that only the Hulk could f***.
On that same podcast, Goyer also implied that any fans who knew who the Martian Manhunter is were virgins. So he's an obvious choice for this project. Other acclaimed films Goyer has written for include Batman v. Superman: Dawn of Justice, Ghost Rider: Spirit of Vengeance, Kickboxer 2: The Road Back, and The Crow: City Of Angels. Deadline says that Warner Bros will look to attach a director quickly, after the script is done.
Though the existence of the Green Lantern Corps movie, planned for 2020, has been confirmed as far back as SDCC 2015, and this isn't the first we're hearing about John Stewart in the DC Cinematic Universe, the rest of these details are firmly in the rumor stage, so check with your doctor to see whether you can take them with a grain of salt.