One Sunday in 1972, an illegal civil rights march in Derry, Northern Ireland turned ugly when British Paratroopers opened fire on unarmed civilians, killing 13 and wounding a further 15. This docu-drama explores the political context surrounding 'Bloody Sunday' and the government inquiry that followed. Drawing on the first-hand testimonies of British soldiers and officers, priests, politicians, medical experts, and eyewitness, as well as victims' relatives, SUNDAY offers an emotional yet factual account of what really happened that fateful day.