The movie is filmed in the style of a docudrama. Beginning in the days leading up to D-Day, it concentrates on events on both sides of the channel, such as the Allies waiting for the break in the poor weather and anticipating the reaction of the Axis forces defending northern France. The film pays particular attention to the decision by Gen. Eisenhower, supreme commander of SHAEF, to go after reviewing the initial bad-weather reports as well as reports about the divisions within the German High Command as to where an invasion might happen or what the response to it should be.
Numerous scenes document the early hours of 6 June when Allied airborne troops were sent in to take key locations inland from the beaches. The French resistance is also shown reacting to the news that an invasion has started. The Longest Day chronicles most of the important events surrounding D-Day, from the British glider missions to secure Pegasus Bridge, the counterattacks launched by American paratroopers scattered around Sainte-M