There are loads of projects in various stages of development for James Gunn and Peter Safran's DCU right now. We've got Superman, which is releasing next month, Supergirl, releasing next year, Lanterns, Clayface, a Wonder Woman movie, and even more.
However, not everything that's pitched makes it through. Speaking to Rolling Stone, James Gunn confirmed that recently the team just killed a project for the DCU because of its lacking script.
"We just killed a project. Everybody wanted to make the movie. It was greenlit, ready to go," he said. "The screenplay wasn't ready. And I couldn't do a movie where the screenplay's not good. And we've been really lucky so far, because Supergirl's script was so fucking good off the bat. nd then Lanterns came in, and the script was so fucking good. Clayface, same thing. So fucking good."
We know that Luca Guadagnino's Sgt. Rock movie was cancelled, but that was due to scheduling conflicts rather than a poor script, so it's likely this is another project entirely. Whatever Gunn's referring to, it's clear he wasn't quite happy with it at the time, and with the slate of DCU releases on the way, perhaps it's not such a bad idea to leave a few on the cutting room floor.