Actor John Malkovich will star as the 18th-century womanizer Casanova in a new Austrian theater production. “The Giacomo Variations” is described as a mix between a play and an opera and will feature music by Wolfgang Amadeus Mozart. Malkovich will play an aged Casanova. His singing counterpart will be Austrian baritone Florian Boesch. Austrian radio quoted Malkovich as saying at Monday’s presentation of the project that “it’s the closest I’ll ever get to realizing my boyhood dream of being in the Vienna Boys’ Choir.” “The Giacomo Variations” is slated to premiere at Vienna’s Ronacher Theater on Jan. 5.