William of Baskerville is a 14th Century monk who arrives at an Italian monastery to discuss theology, but when monks start turning up dead, he and his novice set out to find the killer. The first killing is believed to be a suicide, but William is suspicious. Following another death, the abbot asks William to investigate, impressed already by his incredible skills of observation and deduction. William and young Adso, his novice, begin asking questions about what could have led to the deaths.
In addition to rumors of inappropriate liaisons and heated theological debates (such as whether Jesus ever laughed), the pair explore a secret library within the abbey, where William is captivated by the many volumes it contains. But their investigation leads only to tangents and dead ends, and monks continue to die, including one whose body is gruesomely discovered upside-down in a giant pot of pig's blood.
Frustrated, William digs deeper. He develops a theory that the killer is following a plan that the deluded killer believes is inspired by the Bible's description of the end of times. He also links the killings to a book by Aristotle, thought to no longer exist, but which he believes is hidden in the labyrinthine library. But his investigation is interrupted by the arrival of an inquisitor, who quickly fingers several peasants who work at the monastery and win confessions from them through the threat of torture.
William is not convinced. In the end, he finds the murderer is Jorge, the eldest of the monks, who runs from William and Adso into the library, carrying the only existing copy of Aristotle's Second Book of Poetics, believed to have been lost to history. As he flees, Jorge sets fire to the library, and William chases him, horrified at the thought of losing so much knowledge.
Jorge dies in the fire, which spreads and destroys much of the monastery. William is distraught, both at the destruction and his own failings. There was no plan to the killings, and his investigation only landed on Jorge by mistake. He and Adso move on, and the book closes with Adso's recollections as he looks back at the end of his life. The final epigraph, "Stat rosa pristina nomine, nomina nuda tenemus," roughly means that as we look back on a rose from our past, we cannot see the rose itself, and only its name remains.
Best part of story, including ending:
It's hard to believe that a novel about 14th Century monks, who spend most of their time debating theology and aesthetics, could be an engaging read. But Eco's descriptions of this world, and his well-rounded characters, make it nearly impossible to put down. William himself is as real as any fictional character could be.
Best scene in story:
Adso has a brief sexual encounter one night with a peasant girl who works in the monastery, and is racked by guilt throughout the rest of the novel about the sin he has committed. In the end, as he looks back decades later, he still feels some flicker of love for the girl, whose name he never knew and who likely died when she was burned at the stake as an accused witch. It's a touching moment.
Opinion about the main character:
William is incredibly intelligent but also arrogant. Not strikingly so, but enough that he is so caught up in his own theory (and his own brilliance, one suspects) that he is unable to see what is really happening with the murders until it is too late. His mistake led to the destruction of the monastery and the loss of many irreplaceable works of literature.