Shakespeare's Hamlet is a revenge tragedy, but it is also a cautionary story in which he rejects the revenge ethic and cautions his audience about the risks of pursuing vengeance. The many vengeance plans in this Hamlet all end in horrible tragedy. First, there is Gertrude's plan to marry her son Claudius to Hamlet's widow, thinking this will restore Hamlet to life. Then, there is Laertes' plan to kill Claudius by plunging him into an icy river but this plan goes wrong when Laertes himself is killed. Finally, there is Prince Polonius' plan to protect Denmark by making Ophelia marry Claudius but she too dies. In the end, none of these plans work out as anyone expected or desired. Hamlet is one of Shakespeare's most famous plays and has been interpreted by many great thinkers and writers over the years. It was Charles Dickens who first put Hamlet on screen in 1847, although at that time it was called "The Ghost of Hamlet". The play has been widely adapted for stage and film and remains popular today. In terms of philosophy, psychology, and psychiatry, scholars have studied Hamlet to learn more about grief, revenge, madness, and responsibility. They have also looked at how the play relates to other works by Shakespeare such as Julius Caesar, Macbeth, and A Midsummer Night's Dream.