The Dante Club begins with the murder of fictional Chief Justice Judge Healey, who had avoided taking a position to stop or support the escaped slaves of the South. Found by his chambermaid near a white flag atop a short wooden staff, Healey had been hit in the head and then left in his garden to be eaten alive by strategically placed maggots and stung by hornets. Holmes, who examines the body for the police, recognizes the correlation between the murder and the punishments seen in Dante’s Inferno.
Then Reverend Talbot, who was paid by the Harvard Corporation to write against Dante, was found dead in an underground cemetery, buried up to his waist upside down, his feet burnt. Members of the Dante Club, a group of poets translating The Divine Comedy from Italian into English, notice the parallels between the murders and the punishments detailed in Dante’s Inferno. The club, including Henry Wadsworth Longfellow, Oliver Wendell Holmes, Sr. , and James Russell Lowell, sets out to solve the murders, fearing that the truth will ruin Dante’s burgeoning reputation in America, thus making their translation a failure.
Then, Phineas Jennison, both a wealthy contributor to the Harvard Corporation and friend to the translators (a “schismatic”), is sliced open exactly down the middle—all killed in extreme fashion and undeniable resemblance to the punishments of people in Dante’s Inferno. Eventually, the murderer is discovered to be a former Civil War Soldier Dan Teal, a man who worked at Ticknor and Fields. Driven partly mad by the trauma of his war experiences, Teal hears Dante Club member George Washington Greene giving sermons on Dante, and becomes convinced that Dante alone understood the need for perfect justice in the world.
With protecting Dante as his sole motivation, Teal takes it upon himself to release Hell’s punishments as indicated by Dante, in order to purify the city. Teal finds each of his victims when learning of their involvement in the stopping of the translations, which become their respective sins. The club eventually tries to capture him, with the aid of Boston’s first African-American policeman Nicholas Rey, the only other person who saw the connection, while attempting to punish Harvard Treasurer Dr. Manning and Pliny Mead (“the traitors”). Mead was a student of the Dante course who helped betray his eacher by cooperating with Manning. He later fled when the club attempted to punish him for his involvement in stopping the translation of the Inferno. They later encounter him as he tries to round up the translators, to punish them for not embracing his “work. ” Dr. Manning—saved by Longfellow, Holmes, Rey, Lowell, and Fields—realizes the situation as he recovered from his attempted punishment of being buried naked in ice. He sees Teal on the street with a gun to Longfellow, and Manning ends the murderer’s life, thus returning the city to normal.