The “hook” of Sam Mendes’ new movie, 1917, is that it’s all shot to look like it’s done in one take. However, the most important thing to note is that this hook is no gimmick. In a story about the race against the clock, the one-take approach puts you in the psychological headspace of the lead characters and conveys the unrelenting march of war. By removing cuts, Mendes captures the cruelty and indifference of war, and how that contrasts against the humanity of those trapped inside of it. War is hell, but in 1917, Mendes is careful …