Mary Shelley's authorship of the novel "Frankenstein" guaranteed her widespread renown, but her turbulent life and other literary works are equally fascinating. Born in 1797 to the writers Mary Wollstonecraft and William Godwin, she inherited her parents' passion for literature, social justice and women's rights. At the age of just 16 she ran away with Romantic poet Percy Bysshe Shelley, and was widowed by 24. During their eight years together (living mainly in Italy), she was estranged from her family and sometimes from her husband, suffered periods of depression, and saw three of their four children die in infancy. Despite her troubles, Mary Shelley maintained a busy social life, including a complicated friendship with the poet Lord Byron. She also wrote journals, short stories, mythical dramas, and several novels, including "Frankenstein". After her husband's death in 1822 she returned to England with her surviving son. She continued to write, both in order to earn a living and to satisfy her literary ambitions. She also produced major editions of her husband's poetry and prose. Martin Garrett's biography - extensively illustrated with original letters and manuscripts - captures the extraordinary life of Mary Shelley and the social circle in which she moved. The author also discusses some of Mary Shelley's lesser-known writings, long neglected but now the subject of continuing critical attention.