David Harewood
He is best known for his roles as CIA Counterterrorism Director David Estes in "Homeland" ( 2011–2012 ) , and as J'onn J'onzz / Martian Manhunter and Hank Henshaw / Cyborg Superman in "Supergirl" ( 2015–present ) . 
<triplet> Homeland <subj> David Estes <obj> list of characters