[4][5] The series was based on Everybody Comes to Rick's, a play written in 1940 by American authors Murray Burnett and Joan Alison, and the celebrated 1942 film version, Casablanca starring Humphrey Bogart, Ingrid Bergman and Peter Lorre.
[10] Buying the rights to the unpublished and unstaged play by Burnett and Allison in January 1942, Warners had, at various intervals, assigned its adaptation to scenarists Julius and Philip Epstein, Howard Koch and the uncredited Casey Robinson, while also putting at the helm one of their top directors, Michael Curtiz.
[14][15] One of the most iconic films in Hollywood history, Casablanca perfectly caught the present-day (1942) wartime spirit of the age, but the TV series set, as it was, during the latter-day (1955) present of the Cold War, with its spies and intrigue, could not compete.
[17] Billed fourth through seventh in the film's credits are Claude Rains as Captain Louis Renault, Conrad Veidt as Major Strasser, Sydney Greenstreet as Ferrari and Peter Lorre as Ugarte.
The TV series retains the French police chief who bears a slightly different surname, Captain Renaud, played by Marcel Dalio (who was unbilled as Emil, Rick's gambling table croupier in 1942).
The role of Rick, whose surname was returned to its original form, Blaine, was won by David Soul who gained TV stardom as one of the stars of the popular 1975–79 police detective series Starsky & Hutch.
Rick becomes aware of plotting by Soviet spies; the wife (Maureen O'Sullivan) of an American newspaper reporter (William Hopper) captured behind the Iron Curtain is reunited with her husband.