Filmed and set during World War II, it focuses on an American expatriate (Bogart) who must choose between his love for a woman (Bergman) and helping her husband (Henreid), a Czechoslovak resistance leader, escape from the Vichy-controlled city of Casablanca to continue his fight against the Germans.

Principal photography began on May 25, 1942, ending on August 3; the film was shot entirely at Warner Bros. Studios in Burbank, California, with the exception of one sequence at Van Nuys Airport in Los Angeles.

Its reputation has gradually grown, to the point that its lead characters,[9] memorable lines,[10] and pervasive theme song[11] have all become iconic, and it consistently ranks near the top of lists of the greatest films in history.

"Rick's Café Américain" attracts a varied clientele, including Vichy French and Nazi German officials, refugees desperate to reach the neutral United States, and those who prey on them.

At the last moment, Rick makes Ilsa board the plane to Lisbon with Laszlo, telling her that she would regret it if she stayed, "Maybe not today, maybe not tomorrow, but soon and for the rest of your life."

[34] Casablanca also shares many narrative and thematic similarities with Algiers (1938), which itself is a remake of the acclaimed 1937 French film Pépé le Moko, directed and co-written by Julien Duvivier.

[35] The original play was inspired by a trip to Europe made by Murray Burnett and his wife in 1938, during which they visited Vienna shortly after the Anschluss and were affected by the antisemitism they saw.

As Tangier was in Spanish territory, the theatre's wartime bar heaved with spies, refugees and underworld hoods, securing its place in cinematic history as the inspiration for Rick's Café in Casablanca.

[46] According to Julius Epstein, he and Philip were driving when they simultaneously came up with the idea for Renault to order the roundup of "the usual suspects", after which all the details needed for resolution of the story, including the farewell between Bergman and "a suddenly noble Bogart", were rapidly worked out.

[52] Bogart's line "Here's looking at you, kid", said four times, was not in the draft screenplays, but has been attributed to a comment he made to Bergman as she played poker with her English coach and hairdresser between takes.

[56] The film ran into some trouble with Joseph Breen of the Production Code Administration (the Hollywood self-censorship body), who opposed the suggestions that Captain Renault extorted sexual favors from visa applicants, and that Rick and Ilsa had slept together.

[64] The entire picture was shot in the studio except for the sequence showing Strasser's arrival and close-ups of the Lockheed Electra (filmed at Van Nuys Airport) and a few short clips of stock footage views of Paris.

[20][68] The background of the final scene, which shows a Lockheed Model 12 Electra Junior airplane with personnel walking around it, was staged using little person extras and a proportionate cardboard plane.

The song "As Time Goes By" by Herman Hupfeld had been part of the story from the original play; Steiner wanted to write his own composition to replace it, but Bergman had already cut her hair short for her next role (María in For Whom the Bell Tolls) and could not reshoot the scenes that incorporated the song,[a] so Steiner based the entire score on it and "La Marseillaise", the French national anthem, transforming them as leitmotifs to reflect changing moods.

[83] The piano Sam "plays" in Rick's Café Américain, put up for auction with other film memorabilia by Turner Classic Movies at Bonhams in New York on November 24, 2014, sold for $3.4 million.

[8][87] It went into general release on January 23, 1943, to take advantage of the Casablanca Conference, a high-level meeting in the city between British Prime Minister Winston Churchill and American President Franklin D. Roosevelt.

[88] On March 19, 1943, the film was banned in Ireland for infringing on the Emergency Powers Order preserving wartime neutrality, by portraying Vichy France and Nazi Germany in a "sinister light".

[94] Variety also applauded the performances of Bergman and Henreid and noted, "Bogart, as might be expected, is more at ease as the bitter and cynical operator of a joint than as a lover, but handles both assignments with superb finesse.

"[104] On the film's 50th anniversary, the Los Angeles Times called Casablanca's great strength "the purity of its Golden Age Hollywoodness [and] the enduring craftsmanship of its resonantly hokey dialogue".

[16] Ebert said that he had never heard of a negative review of the film, even though individual elements can be criticized, citing unrealistic special effects and the stiff character of Laszlo as portrayed by Paul Henreid.

However, he added that because of the presence of multiple archetypes that allow "the power of Narrative in its natural state without Art intervening to discipline it", it is a film reaching "Homeric depths" as a "phenomenon worthy of awe".

The website's consensus reads, "An undisputed masterpiece and perhaps Hollywood's quintessential statement on love and romance, Casablanca has only improved with age, boasting career-defining performances from Humphrey Bogart and Ingrid Bergman.

Eight others observed that it was similar to Casablanca, and 41 agencies rejected the screenplay outright, offering comments such as "Too much dialogue, not enough exposition, the story line was weak, and in general didn't hold my interest."

The story's protagonist recreates settings from the film inside a virtual reality simulation, including a version of Rick who becomes an advisor and ally (both characters are played by lead actor Raul Julia).

[122] In Casablanca, a novella by Argentine writer Edgar Brau, the protagonist somehow wanders into Rick's Café Américain and listens to a strange tale related by Sam.

"[133] The film also ranked at number 28 on Empire's list of the 100 Greatest Movies of All Time, which said, "Love, honour, thrills, wisecracks and a hit tune are among the attractions, which also include a perfect supporting cast of villains, sneaks, thieves, refugees and bar staff.

Rick is compared to President Franklin D. Roosevelt, who gambled "on the odds of going to war until circumstance and his own submerged nobility force him to close his casino (partisan politics) and commit himself—first by financing the Side of Right and then by fighting for it".

Two other thirty-minute adaptations were aired, one on Philip Morris Playhouse on September 3, 1943, and the other on Theater of Romance on December 19, 1944, in which Dooley Wilson reprised his role as Sam.

It was a Cold War espionage program set contemporaneously with its production, and starred Charles McGraw as Rick and Marcel Dalio, who had played Emil the croupier in the movie, as the police chief.

[178] In the same vein, though Laszlo asserts that the Nazis cannot arrest him, saying, "This is still unoccupied France; any violation of neutrality would reflect on Captain Renault", Ebert points out, "It makes no sense that he could walk around freely. ...