Does the subject want to ask "which chapter is it when everyone knows the real age of Bai Chunian"? Chapter 12. According to the content of the query novel The Fall of Mermaid, in chapter 12, Bai Chunian revealed his identity, and the investigation team found out his identity, only to know that Bai Chunian was 1 10 years old. Bai Chunian is the hero of the novel The Fall of Mermaid. The novel is a book published by Hunan Literature and Art Publishing House in 2022 by Qian Lin.