Whitten wrote one of the most interesting takes on the werewolf legend with his Southern Gothic novel Moon of the Wolf (1967). In it we get a combination of a murder mystery and an exploration of lycanthropy from a psychologist's perspective. A series of murders seem to be the work of a savage animal. Whitten sets his novel in the 1930s so when the first murder victim also turns out to be a black woman we get the additional layer of social criticism of racism in the south. The police sheriff's investigation leads him to a wealthy white family of plantation owners and whispers of illicit sexual relations.
Angry locals insist the girl was attacked by a pack of wild dogs and set out like a posse of Transylvanian villagers to kill them all. But the skeptical sheriff is not convinced. Medical evidence points to violence by a human hand even amid the signs of an animal attack. His questioning of the locals uncovers their superstitious beliefs, the curious practice of hoodoo with its bottle tree and other witchcraft-like talismans, and an odd reference to "Loup Garou." A psychologist enters the picture and begins to explain the legend of the werewolf and lycanthropy as a legitimate mental illness.
Moon of the Wolf was made into a TV movie (almost faithful to the book) in the 1970s with David Janssen as the sheriff and Bradford Dillman as the primary murder suspect. You can find several versions of the full movie at YouTube. The best quality version I found is here.