Who were the three masked guests? Who was the jailer's new assistant? Who was the bold warrior defeated by Tancredi? In a sequence of ' unmasking' music Christopher Hogwood reveals all at the request of the under-20s. Operatic disguises are stripped away by Mozart (Don Giovanni and The Magic Flute), Beethoven (Fidelio), and Monte-verdi (II combattimento); more than that is removed by Salome, and masked identities are revealed even in Vaughan Williams's Sixth Symphony, gramophone records