A Home at the End of the World is a book by Pulitzer Prize-winning author Michael Cunningham, who also wrote the screenplay of the movie (directed by Michael Mayer).

The book is narrated in the first person, with the narrator changing in each chapter. Bobby and Jonathon are the main narrators, but several chapters are narrated by Alice (Jonathan's mother) and Clare.

Bobby and Jonathan have been utterly inseparable since they were teenagers in suburban Cleveland. As close as brothers, they also experiment sexually. The two eventually lose touch, but meet up again in their twenties in 1980s New York, where Bobby (played by Colin Farrell) moves in with Jonathan (Dallas Roberts) and his eccentric roommate Clare (Robin Wright Penn). Clare had planned to have a baby with Jonathan (now openly gay), but Bobby and Clare become lovers, while Jonathan still has feelings for Bobby. The trio form their own unusual family, questioning traditional definitions of family and love, while dealing with the complications of their love triangle. Erich, a former sexual partner of Jonathan's, joins the household when he becomes ill with AIDS, although this subplot is absent from the film version. In the movie Erik Smith plays Bobby as a teenager, and Harris Allan plays the teenage Jonathan.