It was the biggest bank robbery in British and Irish history. Days before Christmas 2004, gangs of armed men take over the homes of two Northern Bank officials in Belfast and County Down. With family members held hostage, the officials are instructed to remove cash from the vaults of Northern Bank headquarters in Belfast city-centre and load it into the back of a van - not once, but twice - before the van disappears into the night, along with more than £26.5 million in new and used notes. With the finger of blame pointed at the IRA, the raid makes headlines around the world and sends shock-waves through an already faltering Northern Ireland peace process.

Through dramatized court testimonies, new interviews and archive, Glenn Patterson takes us into the unfolding story of a meticulously planned heist and its chaotic aftermath. Military precision giving way to soap powder boxes stuffed with cash. The bickering of politicians against the silence of the man said to be the robbery’s mastermind. There are even rumours that proceeds from the robbery are to be used as a pension fund for IRA members as it prepares to disarm and disband.

Glenn Patterson has unfinished business with the Northern Bank Job. In fact, he thinks all of Northern Ireland does.

Episode One: Unexpected Visitors

Presenter: Glenn Patterson

Actors: Louise Parker, Conor O'Donnell & Thomas Finnegan

Music: Phil Kieran

A BBC Northern Ireland production for Radio 4