Bitten is a fantasy novel by Canadian writer Kelley Armstrong, published in 2001. It is the first book in the Women of the Otherworld series, and her first novel.
 Elena Michaels is the only known female werewolf, but she grows tired of spending her life pursuing rogue werewolves and trying to control her temper and violence. She decides to leave her Pack and live in Toronto as a human, but the Pack leader calls in a favor, which leads Elena to try to help quell an uprising.
 The main character of Bitten is Elena Michaels, a woman who is the only known female werewolf in the world. She lives in Toronto, Ontario, Canada, and writes for a popular newspaper. She struggles to deal with her other-ness and to assimilate to the human world. She also contends with her terrible childhood and with the man who bit her and turned her into a werewolf.
 Elena has settled into a somewhat normal existence, living with her architect boyfriend and ignoring her wolf side as much as possible. However, she learns that her Pack (the governing body of werewolves) is in trouble and comes to their aid, flying to Stonehaven, the country estate of the pack Alpha. It is in Bear Valley, a fictional city in up-state New York. When Elena arrives, she is greeted by her ex-lover, Clayton Danvers, who bit her and made her a werewolf (without her consent). Clayton is also the bodyguard and foster-son to Jeremy Danvers, the pack Alpha (leader). Elena learns that a local woman was found murdered on Stonehaven's land,  savaged by what authorities thought to be a dog. However, the Pack has determined that she was murdered by a Mutt, a rogue werewolf. They find out he is a recently escaped killer who was recently turned into a werewolf. Clay and Elena chase him into a rave and after several of the partygoers are killed, the wolf is hit by an SUV.
 Soon, the rest of the Pack arrives to help with the problem: Antonio Sorrentino, his son Nicholas Sorrentino, Logan Jonsen, and Peter Myers. The werewolf Pack are the self-appointed governing body of the werewolf world. If they feel any non-Pack wolves (called "Mutts") become noticeable to humans, they kill them. In an ambush Peter is killed and Jeremy, the Alpha, is seriously wounded. Finally, the pack figures out that the "mutts", tired of being governed by the Pack, are trying to free themselves from their rule. To do this, one mutt, Daniel, has started turning human killers and other escaped convicts into werewolves to fight the pack.
 Armstrong says Bitten was inspired by an X-Files episode on werewolves. She had the idea to portray werewolves as other than "bloodthirsty, ravening beasts" and quickly wrote a short story about a young woman who becomes a werewolf to present to her writing group. Eventually, Armstrong fleshed out the short story into a novel that became Bitten.
 In the Women of the Otherworld series, unlike many modern horror fiction stories, werewolves transform into full wolves in a painful transmogrification, while maintaining their hair colour and body mass, making them extremely large wolves. Although transformations have to occur regularly, Armstrong's werewolves are not affected by phases of the moon, can shape-shift at will and can learn to transform a single part of their body. Werewolves can be killed by anything that can kill a human and have no extra sensitivity to silver. They age slower than humans. For example, Antonio and his son Nick, despite an age gap of 17 years, pass themselves off as brothers in human company. In fact, Pack sons are raised referring to their fathers as 'uncle' while amidst humans, in order to avoid questions.
 While in human form, werewolves have wolf-like characteristics, better hearing, a keener sense of smell and a wolf's instinctive reactions, while in wolf form they maintain their intellect but cannot talk and are more driven by instinct. In both forms, they have greater strength and reflexes than a normal human or wolf and heal significantly faster. Hereditary werewolves acquire these enhanced abilities gradually, following puberty, and have their first change in their late teens or early 20s. Non-hereditary werewolves start changing shortly after they are bitten, and not all survive the process; the bitten Mutts took around a month to recover. In the case of Clay, he could transform and had the enhanced abilities from when he was bitten at around age five.
 For a while, there was discussion of making a movie adaptation of this novel. Angelina Jolie was approached to play the central role of Elena. A script is still floating around for it.
 On 23 August 2012, Space announced that a full-season TV adaptation of Bitten would commence production in spring 2013. The 13-part series was scheduled to premiere in fall 2013 but was pushed back and premiered in January 2014. On 9 March 2013, it was announced that Laura Vandervoort would be cast as Elena Michaels.
 On August 12, 2014, the full first season was released in the United States of America on Blu-ray and DVD.