It’s also all done with a straight face. Oh, how refreshing this is. There are no invisible quote marks hanging in the air, no cocked eyebrows. This is especially true in the treatment of the Pevensie siblings. The temptation to have a bit of knowing fun with the period setting must have been great, but other than the intrusion of one or two grating anachronisms — it’s most unlikely that a middle-class school kid in wartime Britain would have proclaimed: “I’ve got it sorted” — these accomplished young actors have been allowed to play their characters without that irritating need to ingratiate themselves with their modern, supposedly more knowing counterparts. Peter (William Moseley) is quietly heroic, ­Susan (Anna Popplewell) self-possessed. One imagines that they might even go on to dev­elop stiff upper lips. They are school pupils from another age — one as distant from us now as Narnia itself.

And perhaps that is why we like them. Our screening took place during a weekend when the media was drenched in coverage of gang knifings, dead teenagers and youthful anti-social behaviour seemingly out of control. The enormous popularity of the kids from Narnia, like Harry Potter and his chums — all of them retro in their way — offer us the reassurance that it needn’t be this way, that, nostalgic though it may be, we must have been doing something right. Now there’s a subtext for Polly to ponder.