The O’Donnell’s are an Irish Catholic family living in London, through the Troubles in Ireland in the 20th century, though the conflict in Ireland had been raging for centuries. 
Their differing beliefs about freedom and civil rights influences the decisions they make and the secrets they keep.
 
Why is Claire's family estranged?
What will Hugh do for his beliefs?
Will Molly’s Protestant allegiances grow or will the lure of Sean’s views change her understanding of Irish history?
 
For family and friends, the reach of The Cause and fear of telling the truth have devastating effects on their loves, liberty and life.