Martian Manhunter has been a key member of Kara's team on Supergirl, but he hasn't always been able to use all his superpowers. Now, the executive producer has revealed why.

Supergirldropped a serious truth bomb when Hank Henshaw (David Harewood) revealed himself to be J'onn J'onzz, better known in the comic universe as Martian Manhunter. As many have pointed out, the ...