Martian Manhunter will make his DCEU debut in the Zack Snyder cut of Justice League. Presumably meant to be in the original film, Harry Lennix joins the cast to play J’onn J’onzz (Manhunter’s real name). He was previously seen in live-action on the Supergirl series played by David Harewood.
Martian Manhunter is one of the founders of the Justice League and is typically seen as the admin of the Halls of Justice. Often underestimated, he can go toe to toe with the like of Superman. Manhunter can phase through objects, shapeshift, invisibility, flight, telepathy, telekinesis, and all the super standards like strength and speed. His “new 52” back story is one of loss and survival, losing his family in a war with the white Martians. He lives on earth in his human form as a detective.
If you want some reading suggestions for Martian Manhunter check out Justice League of America #1 of the New 52, Justice League International #1, and Martian Manhunter series from 1998. He was also a staple in the Justice League series.
The Zack Snyder cut of Justice League comes to HBO Max March 2021!