Following a failed bank robbery, affable crooks Jimmy (James Nesbitt) and Rudy (Lennie James) find themselves locked up for a lengthy stretch in HM Prison Long Rudford. The pair soon discover that the prison governer has written a musical based on the life of Nelson, and offer to stage the show for him, thus providing themselves with cover for an escape attempt. However, as the night of the big break approaches, Jimmy's fledgling romance with prison support worker Annabel (Olivia Williams) threatens to cause problems.