The novel Orlando: A Biography (1928) by Virginia Woolf was apparently written to commemorate her friendship and/or affair with Vita Sackville-West, and Woolf had her first draft of the book bound as a gift for her friend/lover. Though not one of Woolf's most acclaimed novels, Orlando was a very successful one, allowing Virginia and her husband Leonard to buy their first car and enjoy a measure of financial stability at last.
Orlando is great fun to read, a charmingly humorous story written in Woolf's characteristic stream of consciousness prose, though unlike, say, Mrs. Dalloway, which follows its characters through a single day, Orlando follows its protagonist from his youth in the late sixteenth century to her adulthood in the early twentieth century. As a young foppish nobleman Orlando becomes a favourite of Queen Elizabeth I, falls in love with a Russian princess who leaves him, returns to his huge estate despondent, takes up writing, hobnobs with literary figures, and finally moves to Constantinople where he works an ambassador. While there, he falls into a coma and wakes up a woman; Orlando herself seems unruffled by this change, perhaps because "in every other respect, Orlando remained precisely as he had been". She returns to London to face lawsuits claiming that either she is dead and cannot hold title to her property, or she is a woman ("which amounts to much the same thing", writes Woolf tartly but truly: women could not then hold title to property); she again takes part in literary life, though is not taken nearly so seriously now she is female. She marries, is declared a woman, regains her estate though not her wealth (dissipated in lawsuits), becomes pregnant, publishes a book she has been working on for over 300 years, gives birth to a boy; it is 1928, and Orlando is 36 years old.
What are we to make of this fanciful story? Woolf originally described the book as "an escapade, half-laughing, half-serious; with great splashes of exaggeration", and so it was taken for some time. More recently, however, as feminism has loomed ever larger on the western critical horizon, it began to be read more and more persistently as a feminist meditation on gender and sexuality, and also as a critique of the very possibility of biography. No doubt it is all these things, and more, for Virginia Woolf was one of the foremost modernist writers whose intelligent and original writings have had an indelible impact on western literature.
Orlando has gone through several editions. If you can, find one with the original photographs (some of Vita Sackville-West dressed up as Orlando) scattered through the text, rather than gathered in the middle or omitted altogether, the sad fate of several versions. My beautiful new Vintage Classics (Random House) edition has the photos in their original places. You might also want to take a look at Kelly Tetterton's interesting essay examining the paperback editions of the novel and what the covers can tell us about the milieu they were published in. It's online at http://www.tetterton.net/orlando/orlando95_talk.html
In 1993 Sally Potter released a film version of Orlando which she wrote and directed. Starring Tilda Swinton as Orlando and Quentin Crisp, memorably, as Queen Elizabeth, the film departs in places from the book but remains true to Woolf's vision and intentions. It is a gorgeously lyrical portrait of Orlando's long life, beautiful, compelling, mysterious, and interesting, just as it should be.
Read the book; see the movie. They're both wonderful.