The Crying of Lot 49

The Crying of Lot 49 is a novella by Thomas Pynchon, first published in 1965. The shortest of Pynchon's novels, it is about a woman, Oedipa Maas, possibly unearthing the centuries-old conflict between two mail distribution companies, Thurn und Taxis and the Trystero (or Tristero). The former actually existed and was the first firm to distribute postal mail; the latter is Pynchon's invention. The novel is often classified as a notable example of  postmodern fiction. Time included the novel in its "TIME 100 Best English-language Novels from 1923 to 2005".