Han Yue, a poison doctor from the mountains, enters the city with the Five Poisons to break off his engagement. However, his golden toad is flattened by the Maybach of Shen Zhixia, CEO of the Shen Group. While demanding medical expenses, he rescues Shen Zhixia from pursuers and discovers that she is the woman he is engaged to. When he attempts to end the engagement, he realizes that Shen Dechang's supposed leukemia is actually the result of long-term poisoning. After the maid A Xiang is silenced, the family traitor is exposed, forcing Han Yue to stay on as a bodyguard. A switch involving Kangyuan Pills brings the Ghost Medicine Sect and an old case involving the Hundred Herbs Medicine Hall to light. Yan Qi sets a trap, Mo Baicao appears, and the true culprit turns out to be Shen Hongkun, Shen Zhixia's third uncle. Han Yue opens the Hundred Herbs Medicine Hall and retrieves the antidote to revive Shen Dechang. The board of directors exposes the conspiracy, Shen Zhixia retains her position as CEO, and Han Yue takes back the letter ending their engagement, choosing to stay and build a life together.