When Hal Prince directed Cabaret on Broadway in 1966, he gave us one of the first so-called “concept musicals,” in which plot takes a backseat to theme and theatricality. The show was immediately recognized as the path-breaking work of art that it is: classic musical theater.

Who could have guessed that six years later director Bob Fosse, in only his second film, would succeed in dangerously upping the ante, creating a daring musical film that still astonishes more than a half century after it was released.

Prince’s central metaphor remained intact: the sleazy Kit Kat Club in Weimar Berlin is a stand in for the decadence leading to Hitler’s rise to power. But Fosse cherry-picked John Kander and Fred Ebb’s masterful score, discarding the “book songs” that portrayed character and advanced the story, and focusing instead on the nightclub floorshow in all its garishness, presided over by an Emcee (Joel Grey on both stage and screen) who leeringly invites the audience to “come to the cabaret…where life is beautiful."

The film created even more of a sensation than had the stage production. Driving it is Fosse’s cinematic brilliance and a galvanic, Oscar-winning performance by Liza Minnelli, then just 26, as Sally Bowles, a third-rate American singer who lives without a moral compass while seducing us at every turn.

Fosse’s Cabaret was strong stuff — perhaps the most challenging American film musical created up to that time. “Leave your troubles outside,” advises the Emcee. We do so at our own peril.