Wonderful set design and cinematography. The special effects worked well, as did the one continuous shot. But what really let the film down was the unrealistic characters. In 1917 racism was rampant, and there is no way those working class soldiers from English regiments would have been conversing normally with black people and Sikhs. I grew up in Britain in the 50s and 60s and it wouldn't have happened then, let alone over 100 years ago! In fact there would have been no people of colour serving as working class cannon fodder in any English regiment. Indians had their own regiments. Also the soldiers in Yorkshire and Devon regiments would have had very broad regional accents, I couldn't see that any effort had been made to reflect this. Also I can't imagine the general staff ever talking to a lance corporal, that task would have gone right down the line, probably to a lieutenant. I am amazed that an English director couldn't bring himself to be more authentic, but I guess he was appealing to audiences beyond his island home, and had to be more inclusive.