Gao Yanbo (played by Ouyang Zhenhua), a calm and rational senior chemist of the Ministry of Justice, can help the police solve a case with just a strand of hair or clothing fiber. But he didn't expect that his wife's younger brother, Gu Zechen (played by Lin Wenlong), a forensic doctor, and Senior Inspector Liang Xiaoyou (played by Meng Jiahui), all suspected that Yanbo had poisoned his wife. Yanbo had to use his professional knowledge to prove his innocence. Later, Yanbo, Zechen and Xiaoyou all became elites in their respective fields, and worked together to uncover one confusing case after another, but the mysteries continued to appear, even threatening their lives...