Plot: Conductor Osma Vanska returns to the Proms with the BBC Symphony Orchestra for a concert in which elemental forces are at play. Thea Musgrave's Turbulent Landscapes was inspired by six dramatic paintings by Turner; Rachmaninov's passionate First Piano Concerto is performed by Stephen Hough; while the essence of life itself is the theme of Carl Nielsen's Symphony No 4, The Inextinguishable