Grandfather Paradox

Wounded during WW1 and after briefly serving as a policeman in Ireland, Charles' grandfather "Jack" Ambrose leaves his wife and baby son for Canada in 1922, returning empty-handed four years later. Why did he leave, what did he intend to do, what happened and why did he return? A century later his grandson Charles attempts to understand and connect to a man he had met only briefly, trying to reconstruct those "lost" years by writing a fictionalised account of this period in his grandfather's life.