Re: New Here: Klingon Question
The look first changed with ST:The Motion Picture. Since there was a larger budget, the Klingon makeup design could be more sophisticated than greasepaint and a fake mustache. The Enterprise episodes R. Star
mentions will give the in-universe explanation.
Curly: Oh, you hit Santa Claus. Just for that, no toys! --Wee Wee Monsieur (1938)