William of Baskerville and his novice, Adso, arrive at a secluded abbey, where a debate about crucial beliefs is about to take place; the abbot asks William to investigate the death of a young monk, but not everyone supports the search for the truth.
After another tragic incident, William and Adso suspect a dark secret and try to enter the library; Adso befriends a girl with red hair in the woods; Remigio reflects his past; the papal delegation heads to the abbey.
In desperate search for glasses, William gathers more clues and is able to decipher a secret message; Adso upsets the monks by researching Dolcino and Jorge warns him against women; in the mountains, a woman named Anna swears revenge on Bernard Gui.
William and Adso solve the riddle in the library and continue their search for clues; Adso visits the girl; while the monks mourn the victim of another incident, the monks of the order of St. Francis and the papal delegation arrive at the abbey.
The delegations argue about the wealth of the church; Remigio can't hide his past any longer but escapes Bernard Gui with the help of William and Adso; the debate begins with a shocking revelation by the cardinal; Adso confesses to William.
William speaks before the council when monks find the next victim; Remigio and Anna meet at the cemetery; Adso finds out that the red-haired girl was captured and puts himself at risk to save her; William loses an important clue.
John Turturro
Guglielmo da Baskerville
Damian Hardung
Adso
Fabrizio Bentivoglio
Remigio
James Cosmo
Jorge
Rupert Everett
Bernardo Gui