can you mention its storyline?
It focuses on an American expatriate (Bogart) who must choose between his love for a woman (Bergman) and helping her and her husband (Henreid), a Czech resistance leader.
Casablanca (film)
 it focuses on an American expatriate (Bogart) who must choose between his love for a woman (Bergman) and helping her and her husband (Henreid), a Czech resistance leader, escape from the Vichy-controlled city of Casablanca to continue his fight against the Germans. The screenplay is based on "Everybody Comes to Rick's", an unproduced stage play by Murray Burnett and Joan Alison. The supporting cast features Claude Rains, Conrad Veidt, Sydney Greenstreet, Peter Lorre, and Dooley Wilson. 
who played the female lead in the 1942 film casablanca Ingrid Bergman who wrote its script? Howard Koch and who directed it? Michael Curtiz and who was the male lead in this? Humphrey Bogart how was its initial response? It received "consistently good reviews".
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Casablanca (film) [SEP] Introduction
Although "Casablanca" was an A-list film with established stars and first-rate writers, no one involved with its production expected it to be anything other than one of the hundreds of ordinary pictures produced by Hollywood that year. "Casablanca" was rushed into release to take advantage of the publicity from the Allied invasion of North Africa a few weeks earlier. It had its world premiere on November 26, 1942, in New York City and was released nationally in the United States on January 23, 1943. The film was a solid if unspectacular success in its initial run.