Solitary girl Su Xin picks up a talking orange cat named Nian Gao. With the cat’s sharp sense of smell, she uncovers a neighbor’s murder case. Criminal investigation captain Gu Yanzhou changes from doubt to reliance. The girl and the cat get caught up in serial murders. When the mastermind Chen Mu surfaces, this seven-jin orange cat becomes the key to solving the case. Gu Yanzhou gradually falls for this special pair.