Parade's End S1, E5

Revolves around a love triangle between a conservative English aristocrat, his mean socialite wife and a young suffragette.

Cast:Benedict Cumberbatch , Rebecca Hall , Roger Allam , Adelaide Clemens , Rupert Everett , Miranda Richardson , Sasha Waddell , Janet McTeer , Clare Higgins , Tom Mison , Stephen Graham , Malcolm Sinclair , Anne-Marie Duff , Ned Dennehy , Anna Skellern , Lucinda Raikes , Sylvestra Le Touzel , Alan Howard