On the CBS series, Non is depicted as a former scientist in a league with the House of El, said The Hollywood Reporter.
He is described as a brutal Kryptonian military officer who is sinister, powerful and angry. An antithesis of all things Supergirl (Melissa Benoist) stands for, Non will quickly become Supergirl's greatest threat.
The character takes a slightly different direction from the comic book's version.
Vance, 43, will first appear in episode eight of the first season. He joins Chris Browning, Owain Yeoman and Iddo Goldberg who were previously tapped to play the villainous Reactron, Vartox and Red Tornado respectively.
"Supergirl" launches on October 26.