Happily, Radcliffe’s presence never felt like merely a ploy to increase the ratings – although presumably it won’t have done them any harm. For a start, casting a real teenager served as a constantly jolting reminder of just how young First World War soldiers were. (When he sailed for France, Jack still wasn’t 18 – and so needed a letter of permission from his dad.) One minute, we saw a boy having a sneaky fag with his sister and moaning about his parents. The next, he was commanding a platoon of 20 Dubliners, most of them older and far more worldly than he was. And through all of this, Radcliffe created an entirely convincing sense of a young man trying unconvincingly not to be scared – and doing his unconvincing best to impersonate a grown-up.

At the same time, Radcliffe was wise enough to leave the real actorly fireworks to Haig, who mapped Kipling’s changing feelings about the war with great clarity – from the early, almost excited patriotism to the terrible grief and guilt when Jack was killed on his first day of action.