Lance Corporal Schofield (George MacKay) helps us experience the true horrors of World War I for ourselves. Credit: universal Director Sam Mendes based the plot of 1917 on a World War I story told to him long ago by a veteran of the trenches — his Trinidadian novelist grandfather Alfred Mendes, who in 1917 was a Lance Corporal in the British Army. But he also freely admits he based the style of th