Drawing on the material’s famously convoluted history, from an episode in Christopher Isherwood’s Berlin Stories through the John Van Druten stage comedy I Am a Camera and Cabaret the Broadway musical, Allen incorporated the best elements of the various versions into her screenplay, along with her own original ideas. (Later, revisionist revivals of the stage show would borrow generously from the film.)

Concentrating on the contrast between the “divine decadence” of the heroine’s promiscuous lifestyle and the brutal backdrop of incipient Nazism, Allen hit the high point of a writing career that also included stage and/or film versions of The Prime of Miss Jean Brodie, Tru and Travels with My Aunt. She gave the characters in Cabaret a depth and complexity they had not had before, setting them adrift in a world of relaxed social and moral boundaries that seemed to reflect the American counterculture movement of the ’70s.

The concept of Cabaret was revolutionary in that it was the first screen adaptation of a book musical to confine the numbers to a performing arena—in this case the Kit Kat Klub, a sleazy cabaret in 1931 Berlin. Minnelli, as the talented but tawdry would- be star Sally Bowles, and Grey as the salacious, grotesquely made-up master of ceremonies, perform all their song-and-dance routines there. The only exception to the rule is the chilling “Tomorrow Belongs to Me,” an anthem of German patriotism led by a Hitler youth in a crowded open- air beer garden.

The Broadway original, directed by Hal Prince with a book by Joe Masteroff, had set some numbers in the club but also followed the conventional pattern of having characters burst into song in their day-to- day lives. For better or worse, Cabaret sounded a death knell for the standard, “I feel a song coming on” type of movie musical. Missing from the film, along with a sentimental older couple who take up considerable time in the original musical, are several patter songs and ballads. Kander and Ebb added even more vitality to the movie’s score with the substitution of the high-energy, cabaret-bound numbers “Mein Herr,” “Money, Money” and “Maybe This Time.”

The approach used by Fosse and Allen offered a new and bracing realism to movie audiences who were shying away from the artifice of old-style musicals. Fosse reinforces the air of reality with naturalistic performances, even from Minnelli as the inherently over-the-top Sally, that allow for genuine feeling while placing the dynamic production numbers in high relief. More than any previous version, the film of Cabaret never lets the audience forget that just beyond the frivolous confines of the cabaret, genuine horror is waiting in the wings.

Nineteen seventy-three was definitely Fosse’s year, bringing him not only an Oscar for Cabaret but an Emmy for the Minnelli TV special Liza with a Z and a Tony for Pippin. He became the only person to have won all three Best Director awards in a single year. Although he would create other galvanizing works onstage (Chicago) and film (All That Jazz) before his death in 1987, Cabaret remains the most vibrant expression of the unique Fosse talent.

Minnelli had made a name for herself in movies and cabaret with a small “c” before being cast in the film of Cabaret. (Legend has it that she had auditioned for the original stage musical 14 times before losing the role of Sally to Jill Haworth.)  But it was this movie that turned her into an international sensation, putting her on the cover of Time and Newsweek in the same week and making her, for a time, the hottest name in films.

Ironically, Cabaret interrupted Minnelli’s burgeoning career as a gritty young dramatic actress in movies such as 1969’s The Sterile Cuckoo (for which she earned a Best Actress Oscar nomination) and 1970’s Tell Me That You Love Me, Junie Moon. After her intense identification with Sally’s overstated, false-eyelashed style and her successes as a concert performer of electrifying powers, it became difficult for the film industry to envision Minnelli in non-theatrical roles. The movie career that reached breathtaking heights in Cabaret was diminished by such disappointing follow-ups as Lucky Lady and A Matter of Time. Minnelli’s checkered film history has included one other innovative and darkly brilliant musical, Martin Scorsese’s 1977 New York, New York, and a charming performance in Lewis Gilbert’s lightweight 1991 Stepping Out. She continues to deliver sell-out concert performances and win awards (including a Tony for her 2009 Broadway show Liza’s at the Palace). But if there is one image with which she will forever be identified, it is that of Sally Bowles prowling the cabaret stage with erotic abandon in black knickers, vest, garters and bowler hat.