Season of the witch

Set during the 14th century, the movie begins with three women who have been accused of witchcraft and are subsequently killed. A priest has performed a ritual to ensure that they do not come back from the dead. One woman becomes a demon and kills the priest.
Two knights are returning to their homeland during the Crusades, Behman (Nicolas Cage) and Felson (Ron Pearlman). It is the time of the Black Plague and many townspeople believe the cause is the devil or dark sorcery. The knights meet Cardinal D'Ambroise (Christopher Lee) who is infected with the plague. He blames the plague on a girl named Anna (Claire Foy) and asks the knights to take her to a monastery where the monks can determine if she is truly a witch.
The knights agree to take the girl but only if she receives a fair trial. It is agreed upon and the knights are accompanied by a priest Debelzaq (Stephen Campbell Moore), a young man Kay (Robert Sheehan), a knight named Eckhardt whose family were killed by the plague (Ulrich Thomsen), and a robber, Hagamar (Stephen Graham) who leads them to the monastery.