The Oscar winner delivers a tour de force performance as King Philippe V of Spain, whose sanity hangs on the voice of the castrato Farinelli. There’s not much to Claire van Kampen’s simplistic script for “Farinelli and the King,” the play now running on Broadway after premiering at Shakespeare’s Globe in London. But with a lead performance by Oscar and Tony winner Mark Rylance in full sail, it’s enough. With his courtiers plotting to depose the mad king of Spain (Rylance), hi

His Majesty is not himself today. His most unserene highness, the King of Spain, does not know who or what he is, except that he’s not where he belongs. Approach him with caution: He bites. And allow me, if you will, to advise you never to take your eyes off him. Not that you’ll want to. As was observed of another stark raving royal (named Hamlet), “Madness in great ones must not unwatched go.” This is especially true when a great one is portrayed by one of the greatest actor