Lily Cardew, returning home from doing Red Cross work during the war, finds herself feeling restless and unable to fit back into the familiar but rather empty social life of her wealthy family. Looking to occupy herself and to assert her independence from her harsh grandfather, she decides to visit an estranged family member, and ends up falling unwittingly into dangerous company among the leaders of an anarchist group. Meanwhile, her war companion, William Wallace Cameron, is drawn into the burgeoning political upheaval from the other end, and becomes a key figure in the movement working to stem the planned revolt.