Like Rick, Louis undergoes a transformation from cynicism to idealism, though in his case this change is less dramatic and more humorous. Casablanca is an intense film, and Louis supplies some levity, including most of the comic lines. Like the Vichy government he represents, which courted the Nazis for favors and better treatment, Louis is not a man of strong conviction, but a friend to whoever is in power at the time. He works with Strasser, but never with Strasser's sense of urgency or conviction. What he does for Strasser is meant to convey a veneer of loyalty. He arrests Ugarte, closes Rick's bar, and arrests Laszlo simply to impress his German superior. Louis himself seems not to care one way or the other. Louis demonstrates his sporting ambivalence about Laszlo's fate when he bets with Rick about whether or not Laszlo will escape Casablanca.
For a while, Louis seems to care about nothing and no one but himself. A hedonist, he takes advantage of pretty female refugees and regularly receives fixed winnings from Rick's casino. The gambling is illegal, but until Strasser pressures him to close the casino, Louis looks the other way. But Louis's obvious affection for Rick belies his seeming self-involvement. Although he tells Rick not to count on his friendship, he can't hide his feelings for his friend. He expresses this fondness early in the film when he says that if he were a woman, he would be in love with Rick. Later he commends Rick for being the only one in Casablanca with "less scruples than I." At the end of the film, the men cement their friendship when both commit themselves to the Allied cause. Rick commits by allowing Ilsa and Laszlo to escape Casablanca and by killing Strasser, while Louis does it by disavowing his relationship with the collaborationist Vichy government and deciding to escape Casablanca with Rick. Ever the follower, Louis copies Rick when he, too, has become a self-sacrificing idealist.