In 1943, at the height of the bombing war, a film director named William Wyler took a team to England. They were capturing footage for a documentary on the Memphis Belle, one of the first B-17 to complete enough missions for the crew to come home.
The extra footage, including footage filmed on bases in England and on bombing missions over Germany, was sent to the National Archive and forgotten. It was found 70 years later.
Completely restored in a digital frame by frame effort and rendered in 4K, the footage was used to create a new documentary. Surviving pilots and crew in their 90s are interviewed and provide commentary and voice over.
The mix of their memories and the vivid footage that looks like it was recorded create a historical documentary that immerses the viewer in a different time and place.
HBO has it. Clips and trailer can be found on YouTube.