
There are subcategories. I will spare you.
This is a pretty good Cold War sub movie, by a very good director, John Sturges, who made The Great Escape and The Magnificent Seven, thus assuring himself a place on the Parnassus for movie directors. (Whatever that may be. San Gorgonio? That would be my nomination, anyway.)
Cold War sub movies have a problem: You can't rely on shooting and explosions for the excitement, as you can in WWII sub movies, because once Russians and Americans start shooting at each other, it was believed not so long ago, the whole world would explode, prematurely ending the movie. So instead you have to rely on psychology (anxiety, guilt, suspicion, and monomania in particular), accidents, radiation, and technology fetishism. Ice Station Zebra has it all. The movie's a little slow and not particularly inventive, and Ernest Borgnine is annoying (do you know that guy's over ninety and still working? enough!), but there are some nice moments.