Dr. Strangelove or: How I Learned to Stop Worrying and Love the Bomb (1964)

The benchmark. A deranged general launches a nuclear strike on the Soviet Union and the men in the War Room discover that every safeguard they built works perfectly to stop them undoing it. Stanley Kubrick shot it straight, in stark black and white, which is why the absurdity lands so hard. Peter Sellers plays three men, including the US president on the hotline to a drunk Soviet premier, and George C. Scott's general is a masterclass in barely contained glee. The target is mutually assured destruction itself, and it needs no Cold War knowledge beyond the word doomsday.