3. Kevin Grevioux
Kevin Grevioux is a very intimidating looking man (you really wouldn't want to owe him money, put it that way). He is probably most famous for playing the Lycan "Raze" in the Underworld series of films Raze being the right-hand-man of the Lycan leader "Lucien'"(who was played by Michael Sheen). As well as his suitably formidable appearance, Grevioux also has a very suitable voice for the role of Luke Cage, having loaned it to major deep-toned characters such as Terrax and Solomon Grundy in television's Earth's Mightiest Heroes and The Batman respectively. It is this trait in particular that could land him the role of an authoritative and no-nonsense guy like Luke Cage. For most of Grevioux's career he has tended to play henchmen and grunts, but a role like that of Luke Cage of the Defenders could be a great opportunity for him to make the full step in to the limelight.