Following a hunch from @Reynolds Woodcock I sat this week and watched Fail Safe (1964) and I'm glad I did. It's a B&W, which I think helps with the intensity and drama. The cast includes Peter Fonda, Walter Matthau, Fritz Weaver, Dan O'Herlihy, a young Larry Hagman, Dom DeLuise and Sorrell Brooke. America fresh from the Cuban Missile Crisis in October of '62 probably hadn't yet cleaned its pants when this debuted. So, I'd imagine the feelings of distrust, anxiety, and intensity were amped up again. Watching from 50 years into the future we have the advantage of hindsight, but I can't help but wonder how times this may have happened before. Wiki link on page 180 within my post. Would recommend.
I also had another rewatch of Casablanca, which I love. I'm not going to re-hash it all, just one part. Everyone remembers "play it again", but the dialogue exchange between Sam and Rick leading up to that is perfect, probably the most perfect 2:40 seconds of cinema. I love the "let's go fishing" from Sam. YT link for your viewing pleasure this morning.
If we all had a Sam to take advice from, we probably would have never gotten into so much shit.