On the night of September 29, 2008, the Irish government decided to guarantee the entire domestic banking system.'The Guarantee' tells the story of that night, and what led to it.
In 1920s Ireland young doctor Damien O'Donovan prepares to depart for a new job in a London hospital. As he says his goodbyes at a friend's farm, British Black and Tans arrive, and a young man is killed. Damien joins his brother Teddy in the Irish Republican Army, but political events are soon set in motion that tear the brothers apart.