The first trailer for Zack Snyder's Justice League teases just how the titular director's vision for Superman will come to life in 2021, showcasing the Man of Steel's black suit and some extra scenes featuring the hero. However, there's a key moment in the trailer that hints a very important member of the Justice League might exist in the DC Extended Universe: J'onn J'onzz/Martian Manhunter.
At 1:03 in the trailer, Martha visits Lois at her home to check up on her. The quick shot leads to an embrace, which was altered for the 2017 movie to have Martha visiting her at the Daily Planet office. However, Snyder previously admitted he wanted to use this exchange to bring in J'onn J'onzz.
In 2019, Snyder shared storyboards indicating that, when Martha left Lois at her apartment, she'd turn into the Martian Manhunter and then General Swanwick, played by Harry Lennix in Man of Steel and Batman vs. Superman. Snyder has been clear he would love to reshoot these scenes, as rewrites resulted in their loss despite the fact Martian Manhunter's addition would have completed the "Unite The Seven" tagline the film hinged on in its early days.
Now, using this roundabout way to introduce Martian Manhunter would work because Swanwick did have a bond with Lois, even admiring her tenacity to find the truth. He was also very interested in Superman, so it stands to reason he'd want to keep a close eye on the hero, because more incursions might endanger him. In short, Swanwick would need to get close to Lois, and who better than the vulnerable Martha to extract all the secrets surrounding the Doomsday fiasco.
This would make Swanwick a bigger player in the DCEU and someone connecting the heroes to the government as a secret military liaison, somewhat similar to Nick Fury and the Avengers. Lennix has said in the past he'd be willing to come back for reshoots, and Snyder definitely wants his overall vision brought to life, so this could be the perfect set up. Swanwick has already been a defender of the planet, so it'd feel organic to the story to let him become the Martian Manhunter.
Justice League stars Ben Affleck as Batman, Gal Gadot as Wonder Woman, Henry Cavill as Superman, Amy Adams as Lois Lane, Jason Momoa as Aquaman, Ezra Miller as The Flash, Ray Fisher as Cyborg, Jeremy Irons as Alfred Pennyworth, Diane Lane as Martha Kent, Ciarán Hinds as Steppenwolf, Jesse Eisenberg as Lex Luthor and J.K. Simmons as Commissioner Gordon. Zack Snyder's Justice League will premiere exclusively on HBO Max in 2021.