Sugar Hill (1974)

When her boyfriend is murdered by mobsters, Sugar Hill decides not to get mad, but BAD. She asks the voodoo priestess Mama Maitresse to summon Baron Samedi, the Lord of the Dead, to help her gain a gruesome revenge. In exchange for Sugar's soul, the Dark Master raises up a zombie army to do her bidding. The bad guys who think they got away clean are about to find out that they are DEAD wrong.