Back when Justice League was gearing up for a theatrical release in cinemas in 2017, a promo poster for the film carried the slogan 'Unite the Seven'. Fans were confused about the reference to 'seven' when the film only had six superheroes. Now, the DC FanDome trailer for Zack Snyder's Justice League has finally introduced the seventh league member, although general audiences will not be able to recognize him.

The moment occurs at the 1:03 mark in the Justice League trailer, where Lois Lane opens the door and is greeted by a smiling Martha Kent. No, Lois is not the seventh league member. Martha is, but it's not the Martha that audiences are expecting.

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Back in 2019, Snyder had released the storyboards from that scene that had been cut from the theatrical version of Justice League. In the storyboards, Martha had come to check on Lois following the death of Superman. After Lois exits the scene, Martha changes shape and transforms into J'onn J'onzz, the Martian Manhunter, before changing into his regular civilian identity General Swanwick, the character played by Harry Lennix in Man of Steel and Batman V Superman.

The storyboard helped confirm the popular fan theory that the Martian Manhunter has been hiding in plain sight since the DCEU started with Man of Steel. In the Comics, J'onn J'onzz is an immensely powerful alien immigrant who has been hiding out on Earth for centuries, secretly observing the rise of metahumans before joining their side in the Justice League.

The fact that the Martha scene was considered important enough to be included in the trailer by Snyder indicates we will indeed get to see the Martian Manhunter's first onscreen appearance in that scene.

The question now is what role the Manhunter will play in the 4-hour long movie. Snyder has stated that the character of Cyborg will be at the center of the movie's narrative. Then there is Aquaman, The Flash, Steppenwolf, and Darkseid, not to mention the main trio of Superman, Batman, and Wonder Woman, who will all need to be properly set up and fleshed out.

Fortunately, the movie's extended runtime should allow for each character to be given their moment to shine. Interestingly, a shot from near the end of the movie, when the six league members are standing waiting for the Batplane to pick them up, the Manhunter is nowhere to be seen, hinting that he may not have a large role to play in the final battle between the Justice League and the forces of Apokolips.

Zack Snyder's Justice League features a lead cast of 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. This news originated at CBR.com.