Genocide
The insects are taking over in this nasty piece of disaster horror directed by Kazui Nihonmatsu. A group of military personnel transporting a hydrogen bomb are left to figure out how and why swarms of killer bugs took down their plane; the answer is more deliriously nihilistic, and convoluted, than you could imagine. Also known as War of the Insects, Genocide enacts a cracked doomsday scenario like no other.
Starring Keisuke Sonoi, Yūsuke Kawazu, Emi Shindo, Reiko Hitomi, Eriko Sono, Toshiyuki Ichimura, Tadayoshi Ueda, Hiroshi Aoyama, Hideaki Komori, Saburo Aunuma
Watch "Genocide" from streaming services Criterion Channel, Amazon released in 1968. It's a science-fiction and horror movie, and has a rating of 4.9 out of 10 from Imdb which is fairly low for this kind of movie.