 In the mid @-@ 1840s , Mary Shelley found herself the target of three separate blackmailers . In 1845 , an Italian political exile called Gatteschi , whom she had met in Paris , threatened to publish letters she had sent him . A friend of her son 's bribed a police chief into seizing Gatteschi 's papers , including the letters , which were then destroyed . Shortly afterwards , Mary Shelley bought some letters written by herself and Percy Bysshe Shelley from a man calling himself G. Byron and posing as the illegitimate son of the late Lord Byron . Also in 1845 , Percy Bysshe Shelley 's cousin Thomas Medwin approached her claiming to have written a damaging biography of Percy Shelley . He said he would suppress it in return for £ 250 , but Mary Shelley refused . 
