The most memorable D-Day took place on the 6th of June 1944. This opening day of Operation Overlord goes by the name Operation Neptune. Under the code name Omaha the US Army wanted to take five beaches in Normandy (France). The 1st and the 29th Infantry Divisions of the US Army stormed one of these five: Omaha Beach.
There where huge losses, because this beach was never intended to be taken this way. By mistake the Allied division landed a few miles from their objective. Also: all of the beaches where chosen, because the defence was not too heavy. However, Omaha Beach had the most complete defences in the entire region.
The movie D-Day makes us think that on all beaches the losses were this catastrophic. Lucky enough for the Allied soldiers, casualties on the other four beaches where far less.