Before The Flash made his way to The CW, the property could have been a feature film from Arrow and The Flash executive producers Marc Guggenheim and Greg Berlanti. And if it had, that movie would have teased a Green Lantern film at the end.
Ultimately, Guggenheim and Berlanti never got to make that Flash movie, although they did write the first draft of the Green Lantern film starring Ryan Reynolds. During a conversation with The Mutuals at ACE Comic Con recently, Guggenheim distanced himself somewhat from Green Lantern, suggesting that he was more pleased with the pair's first draft (which fans can find on the internet) than with the final product.
When the interviewer asked whether that draft featured a cameo appearance by another DC hero, Guggenheim clarified that Green Lantern never had that, but that his and Berlanti's Flash would have introduced Hal Jordan at the end.
Instead, of course, Berlanti and Guggenheim would develop Arrow for Warner Bros. Television, and its success would eventually lead to an interconnected universe of DC superhero shows on The CW, including one for The Flash. While Guggenheim is not directly involved with The Flash, Berlanti is.
You can see the full conversation in the video above.
Up next from Guggenheim, Arrow returns on January 18 at 9 p.m. ET/PT following a new Supernatural. The CW's The Flash TV series will return on January 16 at 8 pm., and the Flashpoint movie is due in theaters in 2020.