This semi-documentary, which made stars of Jack Hawkins and John Gregson, is a look at life in an RAF fighter station during the Battle of Britain. Set in the Summer of 1940, a squadron of Hurricanes are followed as they take on the massive wave of Luftwaffe fighters and bombers that are intent on breaking down Britain's defences as a prequel to a German invasion. Without the bravery of these pilots Britain may well have been invaded.