The film utilized an all-star ensemble cast to portray the historical figures and average pilots involved, emphasizing the collective effort rather than a single protagonist.
Finding flyable Spitfires and Hurricanes was a greater challenge. Only 12 Spitfires and three Hurricanes could be made airworthy for the seven months of filming.
Laurence Olivier played Air Chief Marshal Sir Hugh Dowding, while Trevor Howard and Patrick Wymark portrayed Air Vice-Marshals Keith Park and Trafford Leigh-Mallory.