A Note Regarding Spoilers
The following FAQ entries may contain spoilers. Only the biggest ones (if any) will be covered with spoiler tags. Spoiler tags have been used sparingly in order to make the page more readable.
What is "phrenology" (the term Candie uses during his monologue about Ben and his skull)?
Phrenology is a pseudoscience that was popular in the 1800s. Its core belief was that an individual's nature could be determined by studying the size, shape and bumps present in his or her skull. Phrenology has long since been dismissed as invalid by the medical community. More info on it can be read here. By the time this story begins, the late 1850s, phrenology had already been dismissed as quackery and had declined considerably in popularity, however Calvin obviously believes it's still legitimate -- it's a good way to show how ignorant and racist the character is.
The primary antagonist is plantation owner Calvin Candie (Leonardo DiCaprio). Candie's servants and family members also act as antagonists and enemies to Django such as Candie's trusted but duplicitous house slave Stephen (Samuel L. Jackson), Mandingo trainer Billy Crash (Walton Goggins), Calvin's Bodyguard; Butch Pooch (James Remar) and Calvin's sister, Lara Lee Candie-Fitzwilly (Laura Cayouette). Other villains include Spencer 'Big Daddy' Bennett (Don Johnson), the Brittle brothers -- Big John (M.C. Gainey), Lil Raj (Cooper Huckabee), and Ellis (Doc Duhame) Brittle, and the Speck Brothers -- Ace (James Remar) and Dicky (James Russo)