I always see this movie as a great Harlem detective story. Shafts pulsate with street-level lingo and a deep sense of conviction you can help but admire. In the great tradition of detective movies Shaft is clearly a hard-bitten loner who spars with friends and foe alike, then gets just what he wants from everyone.
Even though "Shaft" was an MGM release it was clearly intended for the black audience Hollywood had always ignored. The attitude of Shaft is what set it apart - it made no effort to court the white audience at all. John Shaft kept his mouth shut for nobody, and wasn't interested in carrying a civics lesson or being an ambassador from an alien race. He was openly promiscuous, keeping at least a couple of steady women on his string, and taking in the occasional admiring prostitute. He talked dirty, told white cops where to get off, pushed around the toughest of the black mobsters, and made mincemeat of adversaries both black and white. A year before "The Godfather," the Mafia of Shaft consisted of fairly accurate Italian goombah types; Shaft had no trouble letting loose with the ethnic slurs either. In other words, "Shaft" was a fresh dose of reality, in 70s parlance, 'telling it like it is.' This script showed no influence of studio influence, whatsoever.
Shaft has a good New York look. The overall atmosphere is great, a mixture of dingy, claustrophobic hotel rooms and neglected city streets. A lot of the action appears to take place around Times Square, which was quite a different place in 1970 - much rougher, much more rundown. Shaft must hold the record for the number of movie marquees on view in one film; I'd guess it was filmed in late Summer-Early fall with what's playing in downtown Manhattan. Roundtree fills out the role believably while the surrounding cast work well together, even if the stereotype line is occasionally breached. Several nice moments in the script carry the film over its dull passages, all leading up to a great ending.