Typically known for following the superhero exploits of Superman, James 'Jimmy' Olsen, has just been cast to appear in CBS' upcoming series Supergirl starring Melissa Benoist as Kara Zor-El aka Supergirl . Mehcad Brooks (True Blood, Necessary Roughness, Desperate Housewives) has signed on to portray the sometimes bumbling yet ever lovable photojournalist.