Most debates about Shakespeare involve the matter of the real author of the plays. This is based on Shakespeare supposedly being a poor uneducated small-town man, who could not afford to travel to Europe. Therefore someone else who was rich and wealthy and who could afford to travel to Europe, actually wrote the plays, and paid Shakespeare to be the front man.
I found another book that mentions a completely different theory that also seems to fit the facts. And those facts seem to indicate that Shakespeare was actually a spy. He was also apparently quite wealthy in Stratford (supposedly a grain merchant) and yet he played the part of a struggling actor in London.
The Shakespeare Conspiracy
The Shakespeare Secret