I should have posted about this when it came out, but missed it at the time and have since not had a suitable excuse. I still don’t have one, so I’ll just post it anyway with the expectation that it may be new for some.
Forty years ago, in 1971, the New Zealand National Film Unit produced this educational video designed to terrify young people with the horrors of “exposure” (aka hypothermia) and, with luck, teach them how to avoid it. I was never subjected to this film during my educational years, but as recently as 1997, some schools were reportedly still petrifying their youth with the words:
“Thomas Cougan will tomorrow night be DEAD!”
Two years ago, NZOnScreen digitised the film and put it online . (There’s a press release here .) Happily the entire thing is available for all to see, from mountain mules, disgusting breakfasts and fashion of the late hippie era, to a relatively young Ray Henwood  who draws concise diagrams on a blackboard as he expertly pronounces the symptoms and causes of “exposure”.
The digitisation comes in two parts, followed by the credits. (Part Two is below if you’ve clicked into the full post, or you can just wait for Part One to finish.)
The theme of the film remains relevant today, even if modern clothing technology has gradually reduced the number of hypothermia deaths relative to other causes. At least, I think drownings during river crossing attempts are now a more frequent cause of death than hypothermia.
The film opens by panning over newspaper clippings that describe a 1968 accident in which two of three teenagers died of exposure when crossing Biggs Top in the Kahurangis (see Carl Walron’s excellent book Survive  for a more complete telling of the story). Next it shifts into a brief presentation about the facts of hypothermia, before a more lengthy dramatisation that follows five young people, who lack experience for what they’re trying to do, to their ultimate demise.
I can’t figure out where it was filmed, partly because I can’t hear the commentary properly, but I expect somebody knows. It reminds me of Nelson Lakes, but that could also be my limited experience talking. After four decades, the production and acting is amusing to watch, but it was also produced with the intent of highlighting certain things to viewers more-so than as a brilliant production. See how many classic mistakes you can count, including at least one heuristic trap.
As you watch it, keep in mind that some of the knowledge about hypothermia has advanced since it was made, for better or worse. Notably, the statement that most body heat is lost through the head has lately been put down to a fairly flunky US Army experiment , and it’s since been shown that any surface area of the body will lose heat roughly equally, if it’s exposed. I checked further on this, however, and there’s a more detailed summary over at Wilderness Medicine Newsletter  which discusses the points in detail and notes that this concept of even heat loss over the entire surface area of the body really only applies when a person is at rest. Things change once a person starts exercising, though mostly in a way that evens it all out. There’s a brief period at the beginning of exercise where more heat is lost through the head, before the rest of the body starts saying “hey, give me more blood” and all areas start losing heat equally again. This is apparently what was misunderstood from the army experiment. Very importantly, however, if a person is already hypothermic and shivering, heat loss through the skull can be up to 55%! If they’re not hypothermic and shivering, the head is of a more similar importance (in terms of heat loss) to the rest of the body. So if things start getting really bad, ensuring the head’s covered seems like a very good idea.
Of course, I’m not medically qualified to assess this advice and I’m really just regurgitating random advice I found on the internet, so as usual I welcome any feedback in the comments section. That way even more people can regurgitate random advice they found on the internet, but at least it’ll be clearer to them if it’s controversial.
Once you’ve watched part one, here’s part two.