 15 August 1998: the Real IRA exploded a bomb on a crowded street in Omagh, just into Northern Ireland, to halt the Good Friday accords and peace process; 29 people died. Families formed the Omagh Support Group to press the police in their inquiries. The film focuses on the Gallagher family, who lose their son Aiden. His father, Michael, a mechanic, becomes chair of the support group. The press for answers strains his relationship with his wife. High-ranking police speak in bromides. Shadowy figures offer intelligence that calls into question the integrity before and after the bombing of the Royal Ulster Constabulary and its Special Branch. Will the murders remain unsolved?