In 1984, CCP’s reformist leader Hu Yaobang sent more than 1,300 officials to Dao County in Hunan Province to investigate mass killings that occurred in 1967 during the Cultural Revolution. Tan joined the team for part of its stay in Dao County. As a writer for a state publication, Tan gained a number of documents unearthed during the investigation and conducted interviews, based on which he wrote an article of 100,000 characters. His editors, however, said it could not be published because the political climate was changing with the start of the "bourgeois liberalization" campaign, which eventually led to Hu's fall. Tan decided to continue his investigation and traveled to Dao County many times to do follow-up interviews. Tan collected millions of words of information, including nearly 400 case studies, and interviewed almost all the key figures who agreed to be interviewed.
In 2010, Tan published Blood Myths: the 1967 Mass Killings in Dao County, Hunan Province during the Cultural Revolution through Hong Kong-based Tianxingjian Publishing House. This nine-volume work consists of 83 chapters and more than 500,000 characters. According to Tan's investigation, in the 66 days from August 13 to October 17, 1967, more than 9,000 villagers, including women and children, were killed or forced to commit suicide because they were wrongly accused of engaging in counter-revolutionary activities. More than 14,000 people were directly implicated in the killings, including 426 state cadres, 2,767 village officials, and 3,880 Communist Party members. Unlike works on the history of the Cultural Revolution previously published in China that focused on the persecution of intellectuals, this book presents the systematic violence suffered by villagers. The book contains not only the words and stories of a large number of those killed, but also those of the killers and others involved, enabling readers to develop an all-encompassing, multi-faceted understanding of this tragic event. According to Yang Jisheng (see separate entry), most of the information about the mass killings currently circulating at home and abroad originated from Tan's investigations and interviews.
The book was reprinted in 2011 and a revised edition was published in 2016, expanding the book to 700,000 words. In 2017, Oxford University Press published
The Killing Wind: A Chinese County's Descent into Madness during the Cultural Revolution, an edited and condensed (with Tan's permission) version of the book by Stacy Mosher and Guo Jian.