WW1 is key to understanding the 20th century. This riveting film shows approximately 24 hours of WW1 in graphic and continuous detail. It must be seen to help grasp events and conditions that lead to WW2 and from there to today. I was particularly struck by the day the filmmakers chose to start their story: April 6th, 1917. That is the day the USA entered the war. If that's mentioned in 1917, I missed it. Of all dates, battles and isolated skirmishes in WW1, I wonder why this moment was chosen. Is there a message to us or is it coincidence?