During WWI Irish-American Army officer Trevor Sullivan is wounded on the Western Front serving with the famous Lost Battalion. At the end of the war he marries an Irish woman studying art in Paris. Both their families have a history of Irish rebellion against British rule. By 1920, Ireland is again in the throes of armed rebellion. Unlike the Easter Rising of 1916, this time the Irish population supports independence. Sullivan's first visit to Ireland ends in personal tragedy drawing him into the conflict fueled by revenge and hereditary resentment to British rule. Experiencing the oppression of ethnic Catholics in Ulster by the Protestant loyalist majority