Following last week's announcement that Dwayne Johnson's Black Adam will star in a solo film separate for the long-in-development "Shazam," we now know for certain who's writing the latter project.

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The Hollywood Reporter's story mentioned that "one source" indicated Henry Gayden is working on the screenplay, something since confirmed by the writer himself on Twitter.

 

@annericelover Confirmed and loving what's to come... :)

— Henry Gayden (@HenryGayden) January 20, 2017

Best known for the 2014 sci-fi action adventure "Earth to Echo," Gayden wrote the 2010 horror-comedy webseries "Zombie Roadkill."

In development at New Line Cinema since the early 2000s, "Shazam" has passed through the hands of several writers, including William Goldman, John August, Darren Lenke, Geoff Johns and Billy Birch. Peter Segal was at one point attached to direct, but revealed in 2013 that the project had stalled, at least in part due to the resurgence of Superman on the big screen.

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“After Bryan Singer’s 'Superman Returns,' it seemed like there was a moment in time where Shazam was going to see the light of day," Segal said. "That’s when you heard those stories. Now that Superman is being invigorated and going up against Batman, I think it’s difficult for DC to figure out how to launch this character in the wake of Superman’s resurgence.”

However, "Shazam" was then announced in October 2014 as part of Warner Bros.' ambitious DC Extended Universe slate, with Johnson confirmed to star. No director has been announced, and the title role has yet to be cast.