What is the overarching theme? How does the characters actions help determine the theme?

The overarching theme in the text is fear, as evidenced in the characters of Ghost and Mr. Charles. Ghost must conquer his fear of his father, not being accepted, being judged, and most importantly..... failure.

Mr. Charles also feared failure and mockery, but his example and success serve to bolster Ghost and provide him with an example of how to live his life.