is the male lead related to navy by any chance?
He was enlisted in the United States Navy in the spring of 1918.
Humphrey Bogart
With no viable career options, Bogart followed his passion for the sea and enlisted in the United States Navy in the spring of 1918 (during World War I). 
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". 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.
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Humphrey Bogart [SEP] Navy
With no viable career options, Bogart followed his passion for the sea and enlisted in the United States Navy in the spring of 1918 (during World War I). He recalled later, "At eighteen, war was great stuff. Paris! Sexy French girls! Hot damn!" Bogart was recorded as a model sailor, who spent most of his sea time after the armistice ferrying troops back from Europe. He may have received his trademark scar and developed his characteristic lisp during his naval stint. There are several conflicting stories. In one, his lip was cut by shrapnel when his ship (the ) was shelled.