The Virgin in the Ice (S02E01)

Brother Oswin, Cadfael's novice, is discovered on the brink of death, rambling about a mysterious woman. Soon after, the body of a nun is unearthed, brutally raped and killed, frozen in a stream. Oswin becomes the prime suspect in her murder. Determined to clear his novice's name, Cadfael begins searching for the nun's companion, Ermina Hugonin, in hopes of uncovering the truth and proving Oswin's innocence.