An early Star Trek, with Frank Gorshin as Lokai - a fugitive from the enforcer Bele. Lokai is black on the right side of his body and white on the left. Bele has the colors reversed. Capt. Kirk thinks the changed colors are inconsequential but turn out to be a big deal on the planet of Lokai and Bele, the very basis for a type of caste system. Definitely one of the most brilliant of the Star Treks. http://en.wikipedia.org/wiki/Let_That_Be_Your_Last_Battlefield