Plot: Charles Hazlewood presents as the Proms mark the 75th birthday of one of Britain's greatest living composers, Sir Harrison Birtwistle, with a rare performance of the central act of his monumental opera The Mask of Orpheus. It is performed by the BBC Symphony Orchestra, the BBC Singers and a cast that includes Alan Oke and Christine Rice, and conducted by Martyn Brabbins with Ryan Wigglesworth