While answering questions about his DC movies, director Zack Snyder revealed when he first started thinking about turning a specific Man of Steel character into Martian Manhunter.
When did Zack Snyder decide Swanwick would be Martian Manhunter?
The director was asked how long he knew that the character of Calvin Swanwick would be Martian Manhunter. Swanwick first appeared in Man of Steel as the General who was in charge of the military response against Zod. Later on in Zack Snyder’s Justice League, Swanwick is revealed to be J’onn J’onzz — better known as Martian Manhunter.
According to Snyder, this wasn’t planned until a couple of movies into the DC Extended Universe.
“The conversations around Martian Manhunter started post on [Batman v Superman] … when we were watching it in editorial, I was like, ‘You know, Swanwick … I don’t know,'” Snyder stated. “If you look at when Superman goes to the glass in Man of Steel and everyone backs up instead of Swanwick — that was a choice by the actor [Harry Lennix] — I was like, ‘Oh, that was cool.’ And I was trying to decide whether that was wrong, but I liked it, and I was like, ‘No, that’s cool. That’s good, do that.’ And I think that, really, in retrospect, inspired this whole possibility.”
Zack Snyder’s Justice League released in 2021 and served as a director’s cut of the 2017 Justice League movie since Joss Whedon replaced Snyder as director during the original’s post-production. The film had set up multiple potential future storylines, including the full introduction of Justice League member Martian Manhunter and a tease at the continuation of the Knightmare story that appeared throughout the DCEU.