Cloud Atlas consists of six nested stories that take the reader from the remote South Pacific in the nineteenth century to a distant, post-apocalyptic future. Each tale is revealed to be a story that is read (or observed) by the main character in the next. The first five stories are interrupted at a key moment.
After the sixth story, the other five stories are returned to and closed, in reverse chronological order, and each ends with the main character reading or observing the chronologically previous work in the chain. Eventually, readers end where they started, with Adam Ewing in the nineteenth century South Pacific.
(Ewing) foresees his wealthy father-in-law’s response that human nature will never change and that Ewing’s life will amount to “no more than one drop in a limitless ocean.” Ewing concludes his journal with these final words: “Yet what is any ocean but a multitude of drops?”