In this episode, Gareth works the wives harder than ever as they prepare to share the stage of the Royal Albert Hall with some of the world's top professional musicians on the 3rd August - the eve of the day Britain entered World War I.
The wives meet the National Theatre's War Horse team who they will perform alongside, and the planned repertoire forces the wives to confront their own vulnerability. One of the serving wives makes the momentous decision to leave the Armed Forces.
The episode culminates in Gareth and his 100-strong amateur choir giving the most professional and emotionally engaged performance at the BBC Proms.
