::I must admit that I'm struggling to understand your aversion to the plain English "being the first to play the role of Roger Davis"; it's not only clear and understandable to any reader, it's also more accurate than your latest attempt to avoid it, "being the original Roger Davis".  When an actor plays a role, he isn't being the character, he's... well, playing the role. Is there something here that I'm missing?  Are you trying to convey the thought that Pascal is a method actor?