9. Martian Manhunter
In fairness, the Martian Manhunter is another character who has seen some on-screen attention. He was a prominent character in the Justice League animated series, was tipped to appear in Zack Snyder’s canceled DCEU plans, and featured in both Smallville and the Arrowverse’s Supergirl. Even so, he’s never really had his time in the spotlight.
The character’s backstory is simple. He’s a Martian law enforcement officer named J’onn J’onzz who becomes stranded on Earth. In many stories, he’s the last of his kind (not unlike one of DC’s other major heroes) and his impressive set of powers makes him one of the most powerful beings in the DC Universe.
The Martian Manhunter’s story would make for a great movie. The sci-fi backstory, the potential for a gritty noir story involving his police alter ego on Earth, the staggering set of powers – all of it could combine to make J’onzz one of the most compelling movie superheroes. He’s got great potential either for solo movies or as part of a franchise, and desperately deserves more attention.