"Cabaret" is not so much a movie musical as it is a movie with a lot of music in it…. Fosse's approach has been not to open up but rather to confine, on a small and well-defined stage, as much of "Cabaret" as means to be musical theater.
Thus the film has a musical part and a nonmusical part …, and if you add this to the juxtaposition of private lives and public history inherent in the scheme of the "Berlin Stories" [on which the film is based], you come up with a structure of extraordinary mechanical complexity. Since everything has to do with everything else and the Cabaret is always commenting on the life outside it, the film sometimes looks like an essay in significant cross-cutting, or associative montage. Occasionally this fails; more often it works.
Fosse makes mistakes, partly because his camera is a more potent instrument than he realizes, but he also makes discoveries—and "Cabaret" is one of those immensely gratifying imperfect works in which from beginning to end you can literally feel a movie coming to life.
The film gains a good deal from its willingness to isolate its musical stage—even to observe it from behind the heads of a shadowy audience in the foreground—so that every time we return to the girls and their leering master (by now, a superbly refined caricature) we return, as it were, to a sense of theater. And when at certain moments that theater is occupied only by Liza Minnelli, working in a space defined only by her gestures and a few colored lights, it becomes by the simplest means an evocation of both the power and fragility of movie performance so beautiful that I can think of nothing to do but give thanks.
Roger Greenspun, "'Cabaret'," in The New York Times (© 1972 by The New York Times Company; reprinted by permission), February 14, 1972 (and reprinted in The New York Times Film Reviews: 1971–1972, The New York Times Company & Arno Press, 1973, p. 222.