In this work's opening, the narrator encounters a 
In this work's opening, the narrator encounters a leopard, a lion, and a she-wolf that force him into a dark wood. The protagonist of this work is mistaken at one point for the issuer of the papal bull Unam sanctum. A later scene in this work sees two men, who are (*) frozen opposite one another endlessly head butting each other. Another character is continually bitten by Ugolino. The author's mentor appears as a man forced to wander a desert under a rain of fire. The story of Lancelot and Guinevere is mimicked in this work by Paolo and Francesca da Rimini. For 10 points, name this first part of Dante Aligheri's Divine Comedy in which Virgil leads him through hell.
In this work's opening, the narrator encounters a leopard, a lion, and a she-wolf that force him into a dark wood.
{Inferno }[prompt on “Divine Comedy”]