In the troubling HBO documentary Thoughts and Prayers, the $3bn active shooter preparedness industry shows the bleak reality of being a child in the US

Talking about changes experienced by kids today often runs the risk of sounding reactionary, not to mention naive. No, there wasn’t as much talk about autism, or transgender kids, or any number of topics growing up in the 80s and 90s, because they weren’t understood or discussed in the same way – not because they didn’t exist. But it’s striking, watching the new HBO documentary Thoughts and Prayers, the degree to which it shows a demonstrable change from the experiences of someone growing up 30 or 40 years ago versus today: the absolute universality of emergency action plans that go beyond the scope of the fire drills you might remember. Thoughts and Prayers surveys many of those lockdown drills, and the many supplements available to contemporary schools designed to offer further protection from an active shooter: bulletproof backpacks, in-classroom shelters and astoundingly elaborate real-life simulations, complete with stunningly realistic makeup for bullet wounds.

This change isn’t lost on directors Zackary Canepari and Jessica Dimmock. “Zack and I have an eight-year-old daughter,” Dimmock said in a joint interview, “and the idea for this film came about because she was coming up in school, and we were facing the thing that basically every American parent faces. Almost every kid in America does drills like this, across the board. We definitely did not grow up doing this, either, and I think there will be a huge part of the audience that will look at this and be like, ‘wow, right, I knew this was happening, but [still surprised] to see it.’ And there will be this whole other part of the audience that will be like, ‘yeah, Mom, Dad, I do this three times a year and have since I was five years old.’”

Armed with old files, new technology and tireless detective work, a small West Midlands team has solved more than 240 cold cases – and tells Harriette Boucher why they refuse to give up on the missing