The dialogue is so spare and cynical it has not grown old-fashioned. Much of the emotional effect of Casablanca is achieved by indirection; as we leave the theater, we are absolutely convinced that the only thing keeping the world from going crazy is that the problems of three little people do after all amount to more than a hill of beans.

Much more fun than its stuffy "Greatest Film Ever Made" tag suggests, with a literate script, stylish direction, a great song and cinema's most romantic couple in Bogie and Bergman.

Casablanca accomplishes that which only a truly great film can: enveloping the viewer in the story, forging an unbreakable link with the characters, and only letting go with the end credits.

The film has a peculiar magic to it, and because of its pace the richness of its sense of detail often goes unnoticed.

Seventy years on, this great romantic noir is still grippingly powerful: a movie made at a time when it was far from clear the Nazis were going to lose.