Pam Grier stars as Coffy. She's a nurse who seeks revenge, on the drug dealers who got her sister hooked on bad heroine. Like any 70s Blaxploitation flick, you can expect to see the racist bad guys get their just desserts.
There were scores of these films made during the 70s, and they were really demeaning to both black and white audiences alike. This is mainly due to the vicious racial hostility in these films, and the degrading, stereotypical characters. Especially the female characters.
Other common threads between Coffy, and other films of its type, include brutal violence, corrupt cops, car chases, a generous abundance of nudity, and sex-crazed gorgeous women. Not to mention urban ghettos populated by drug-dealers, pimps, mobsters, and other criminal scum.
Pam Grier, was the undisputed queen of 70s Blaxploitation heroines. She was magnificent, being both tough-as-nails, and drop-dead gorgeous. Like in her other films, Pam outshines the other characters, in Coffy. In fact, Pam is so charismatic on screen, that these sorts of films are unwatchable, without her as the main character.
If you like Pam Grier, you're better off seeing her other films, like Foxy Brown, or perhaps Friday Foster. These films have much less empty sleaze, than Coffy does. Pam's character in Coffy, degrades herself way too much to get the bad guys. Pam's characters in her other Blaxploitation films, don't stoop as low to get revenge, as Coffy did.
I'd say, only watch Coffy, if you're unable to see any of Pam Grier's other films. Otherwise, Coffy is a waste of time. Only Pam's talent as an actress, makes viewing Coffy bearable.