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. Humphrey Bogart is the tough, cynical American with a broken heart, brooding over chess problems in the private room of his bar in the Vichy-controlled Moroccan capital. Ingrid Bergman is his former lover Ilsa making a fateful reappearance; Paul Henreid is her husband, the Czech resistance leader Victor Laszlo to whom Rick gallantly concedes first place in Ilsa’s heart.

It is filled with great lines, although my own favourite actually isn’t much quoted. An agonised Bogart says: “I bet they’re asleep in New York; I bet they’re asleep all over America.” Traditionally glossed as his wakeup call for isolationist Americans, it also speaks of his own agonised wakefulness and weariness. J Hoberman’s new book An Army Of Phantoms, about cinema and the cold war, notes that just five years after this, Casablanca’s screenwriters Howard Koch and Julius and Philip Epstein became one of the first wave of victims of the Huac red scare, fired from the studio by Jack Warner.

• Casablanca is released on 2 December.