Inferno
Allen Carpenter, a writer leading a rather unremarkable life, takes an unexpected tumble out a window during a party. He awakens in a place he doesn't recognize, only to discover he's in Hell. Joined by a mysterious guide, Allen must navigate this infernal landscape on a personal quest to find his way out.
Inferno is the first book in a duology. While it tells a complete story within itself, the narrative continues in a direct sequel.
The novel draws heavily from Dante Alighieri's The Inferno, reimagining its structure and various circles of Hell with a science fiction lens.
Inferno showcases Niven's characteristic hard science fiction approach, but applies it to a fantasy premise, a departure from his more typical Ringworld or Known Space settings. It also highlights his collaborative writing style with Jerry Pournelle, similar to their work on Lucifer's Hammer.