James Gunn shares the most important Superman review yet - from the grandchildren of comic creator Jerry Siegel "This is the Superman movie we've been waiting to see"

Writer/director James Gunn's name may be all over his upcoming Superman reboot movie, but the filmmaker himself tells Extra that the film is a "collaboration of many great creators," and that he takes special satisfaction in the approval of the grandsons of Jerry Siegel, who had "effusive" praise for his film's script.

"One moment I really like, shed a tear, was when Jerry [Siegel]'s grandsons read the scripts for the first time," Gunn tells Extra. "We brought them over to DC, we showed them the scripts in the office. And they came out, and they got on the phone with me, and they were just effusive. I'd never met them, but they were just effusive. They said 'This is the Superman movie we've been waiting to see. Our grandfather would have been so proud.' I'm gonna cry now! That meant a lot."

Siegel's grandsons also have an appearance in the film as extras in the offices of the Daily Planet, and they're not the only members of the extended Superman family to make it into the film, which also includes a cameo from the son of original big screen Superman actor Christopher Reeve.

"I thought it was important to have the history of Superman as a part of this movie. Because at the end of the day, I'm not the creator of this movie. Superman is a great collaboration of many creators and many people throughout the years, going back to Jerry Siegel and Joe Shuster in 1938. All the comic book writers, the makers of the radio serial, the TV shows, the serials and everything else. And I like to have that history as a part of it," Gunn explains. "So we have Will Reeve, Christopher Reeve's son, in a cameo in the movie. Jerry Siegel's grandsons are in the Daily Planet for the entire time. We had all the great Superman comic book writers come and hang out on set and watch a scene, and see everybody, and meet Lex [Luthor, played by Nicholas Hoult] and David [Corenswet/Superman]."

Superman will hit theaters on July 11. In the meantime, check out our guide to all the upcoming DC movies and shows for everything else the DCU has in store.