You will be given a trivia clue, and the category it belongs to. You should answer with the best answer that belongs in the category and is described by the clue. For simplicity, answers should be in all lower cased letters.

Category: THE BOX OFFICE 
Clue: Rated "R" for violence, this 2004 film set in ancient times is the highest-grossing "R" movie ever in the U.S.
the passion of the christ