If I remember correctly, there was lots of footage taken at D-Day. When someone was taking the reels back to the ship, he accidentally dropped the duffel bag with the film overboard and it was lost.
I was stationed in Britain in the early 1970s. ITN (the “Beeb’s” commercial competition, ran the “World at War” series, the same one that the History Channel is running today. I thought it was excellent at the time and still learn something new with each new episodes. That’s red meat for all WW II buffs. I have no memory of that cataclysmic event, as I was a toddler when it ended. Among my first memories is the boys on our street in SW Detroit returning home.
What a shame!