When the commander of the crew of a B-17 Flying Fortress bomber is killed in action in a raid over Sicily in 1943, his replacement, a young, naive pilot struggles to be accepted by the plane's already tight-knit Irish American crew.

Ordered into a suicide mission, their only chance of survival is to band together as brothers in battle. With unparalleled aerial action, Fortress pays homage to the sacrifices of an entire generation during the most important war in history.