Vexilla regis prodeunt inferni — "the banners of the king of Hell go forth." Virgil quotes the Good Friday hymn, inverted: the banners of the King of Heaven become the banners of the King of Hell. Through the fog, something vast. The shapes resolve: wings. Enormous, bat-like wings beating in the frozen air, and the beating of those wings is what makes Cocytus freeze — the cold of lovelessness, generated by the perpetual motion of despair. Then the full figure: Lucifer, frozen to his waist in the center of the lake. Three faces on one head: red in front, yellow-white on the right (the color of impotence), black on the left (the color of ignorance). Three mouths, each chewing a sinner. Judas Iscariot in the central mouth — his head inside, legs dangling, his back skinned by Lucifer's claws. Brutus in the right mouth — head out, legs in, twisting silently, saying nothing. Cassius in the left — large and muscular. The three greatest traitors: to Christ, and to Caesar. The structure of the universe's sin is its floor.
Virgil tells Dante to hold on. He grabs the fur of Lucifer's flank and begins to climb, timing his handholds to the beat of the wings. They descend — and then, at a certain point, the descent becomes an ascent. The center of the earth has been passed. Clinging to Lucifer's fur, they are now climbing upward through the legs, through a passage in the rock, pulling through a narrow fissure. Lucifer is behind them, upside down as they look back. They emerge — not into Hell but into a natural cave, then a narrow path, then upward. Virgil explains: they passed the center of the earth; everything inverts. Lucifer fell from Heaven into the southern hemisphere; the earth's mass shrank from him in horror and formed the cone of Hell in the north, while in the south the displaced earth rose as Mount Purgatory.
They climb out. A hole in the rock shows them the stars. The last word of the Inferno, as of every canticle: stelle — stars. From the deepest pit of lovelessness, the eye turns upward to the light. The climb has been long and the dark absolute. But the stars are there.