R. Star wrote:
Shatner and Nimoy never seemed more than average actors to me. Certainly the characters they played were iconic, but their acting careers beyond Star Trek weren't that great in my opinion.
To be fair, there are hundreds or perhaps thousands of actors who had trouble maintaining their careers after getting a lead role in a series.
Dick Van Dyke, Bob Denver, and David McCallum are just a few from that period that come to mind.