Supreme Sacrifice charts the life of Eamonn Ceannt from his schooldays in Co. Galway right through to his execution on 7 May 1916 in Dublin. It explores such areas as: his youth and family; his love of and contribution to the Irish language; his time at UCD and working as a clerk in the treasury department of Dublin corporation; his introduction to various Irish nationalist movements; his part in the Howth gun-running plot; the planning of the 1916 Rising; his execution in May 1916