On Forever Knight, Janette once described her people, the vampires as walking among humans, but apart from them. Though this line is not quoted directly, it does sum up nicely the theme of this book. Alien in this sense means apart more than actually from another planet.

From the earliest stories of Vlad and Elizabeth Bathory down to the Carpathians of Christine Feehan's series and Spike of Buffy fame, the vampire's history is traced and examined, leading to a variety of discoveries, among them, that the vampire's greatest use is to give authors a semi-human character who is apart enough from humanity to act as a lens through which to observe.

Though some descriptions of how the vampire is portrayed may be rather repulsive, others are not. If nothing else, the reader who wants a road map of which books of the genre to buy and which to avoid, will find this useful.

Synopsis
Different blood flows in their veins—but our blood quenches their thirst.

From Bram Stoker's 1897 creation of Count Dracula, portrayed as a foreign invader bent on the conquest of England, the literary vampire has symbolized the Other, whether his or her otherness arises from racial, ethnic, sexual, or species difference. Even before the bloodsucking Martians of H.G. Wells' War of the Worlds, however, popular fiction contained a few vampires who were members of alien species rather than supernatural undead. Guy de Maupassant's Horla is only one of the best-known.

Vampire invaders from other planets appear in pulp fiction throughout the 20th century. Among others, interplanetary adventurer Northwest Smith meets a shapeshifting, Medusoid seductress in C.L. Moore's Shambleau. Even more intriguing, though, are humanoid and quasi-humanoid beings who live on Earth among us, often camouflaged as our own kind. Jack Williamson's Darker Than You Think, for example, features an inhuman race, vampiric as well as lycanthropic, that has preyed on humanity from prehistoric times. A gentler view of the Earth-born "alien vampire" appears in Ray Bradbury's Homecoming, a poignant tale of the one "normal" boy in a clan of "monsters". Such fiction can use vampirism either to valorize or to undercut racism and xenophobia. Richard Matheson makes the vampire a misfit child in Dress of White Silk and Drink My Blood. Cyril Kornbluth's The Mindworm, at mid-century, uses the alien in the form of a mutant born of human parents to foreground another cultural preoccupation, the fears spawned by the nuclear age. Similar fears underlie Matheson's I Am Legend, in which a worldwide plague wipes out all "normal" human beings and transforms the survivors into a new species.

The boom in vampire fiction that began in the 1970s engendered a variety of "alien" vampires, many of them portrayed as sympathetic characters. The science fiction vampire is especially suited to the presentation of vampirism as morally neutral rather than inherently evil. Suzy McKee Charnas' The Vampire Tapestry, Whitley Strieber's The Hunger, George R.R. Martin's Fevre Dream, Jacqueline Lichtenberg's Those of My Blood, Elaine Bergstrom's Shattered Glass, and Melanie Tem's Desmodus are only a few examples of this richly diverse subgenre. In the '80s and '90s the new subgenre of vampire romance also flourished, exploring the naturally evolved vampire (as well as the more traditional undead type) in terms of the redemptive power of love.

Different Blood surveys the literary vampire as alien from the mid-1800s to the 1990s, analyzing the many uses to which science fiction and fantasy authors have put this theme. Their works explore issues of species, race, ecological responsibility, gender, eroticism, xenophobia, parasitism, symbiosis, intimacy, and the bridging of differences.

An extensive bibliography guides the reader to numerous novels and short stories on the "vampire as alien" theme, many of them still in print.