One conspiracy theory I will not entertain, even in jest, is the Shakespeare authorship question. The original advocate for someone else being the author died in a lunatic asylum (Delia Bacon) and an early advocate for the Earl of Oxford was an eccentric unfortunately but perhaps approximately named Looney.
What saddens and appalls me is that some of the greatest Shakespearean actors of the past half century have subscribed to such theories. Among them is Sir Kenneth Branagh, whose Henry V thirty years ago was just the first of at least 5 films of the plays he was involved with.
On the plane over to Italy, unable to sleep, I saw a lot of films. One of them, All Is True, stars Sir Kenneth Branagh as Shakespeare on his retirement and uneasy resumption of family life in Stratford. The film addresses various questions about the life of Shakespeare and Elizabethan theatre in a way which asserts Shakespeare to undoubtedly be the author.
Branagh is an actor, and actors deal in make believe. But does this depiction mean he has abandoned the Oxford authorship tomfoolery? I hope so.