The screenplay and the movie are hilarious! This is one of the best and sharpest dark comidies EVER! Stanley Kubrick did an amazing job! Same to Peter Sellers. Nobody but Sellers could have pulled off those three brilliant characters!
That's just it. This is the greatest film ever made.
Peter Sellers is a comic genius; he was improvising most of the Doktor's lines and was so funny that they had to edit the last scene to pieces because the man playing the Soviet ambassador was laughing through the whole thing.
Kubrick's wit and insight shine best in this film. It's a film about more than the Cold War; it's about the madness of war itself, along the lines of Kurt Vonnegut's Slaughterhouse Five.
This is a timeless classic and a true inspiration to generations of filmmakers.