Lin Feng, a hidden master, disguises himself as a street locksmith. Jiang Longcheng, the Jiang patriarch, uses his only remaining favor to ask Lin Feng to protect his granddaughter Jiang Shixue for one year. Lin Feng enters Zhongzhou University as her distant cousin and security consultant. The spoiled Jiang Shixue dislikes him at first and drives him away. He offends He Dong, a school bully rejected by Jiang Shixue, who surrounds him with henchmen.
He Dong hires the Changqing Gang to kidnap Jiang Shixue. Lin Feng pretends to be weak but defeats the gangsters with two punches, earning the respect of gang leader Long Si. He then resolves dorm manager Aunt Zhang’s family issues, helps Jiang Shixue keep the Mutual Aid Club, and impresses her. Su Tingwan, the mysterious student council president, buys his rental apartment and secretly investigates his true identity.
He Dong kidnaps Jiang Shixue’s best friend Bai Xiaoyou and forges WeChat messages to lure Jiang Shixue out. Lin Feng breaks down the door to save her. Long Si switches sides and leads his men to beat He Dong, bringing the villain to justice. Lin Feng enters the Jiang family with Jiang Shixue. Jiang Longcheng publicly slaps Jiang Yulong, her disrespectful second uncle, and treats Lin Feng as an honored guest.
To awaken Jiang Shixue’s mother, a vegetative patient for ten years, Lin Feng performs a miraculous needle technique. Jiang Yulong and his son poison the herb meal to frame him, but Lin Feng exposes them with surveillance evidence, ruining their plot to seize assets. The mother, Zhang Peining, wakes up, resolving the Jiang family’s ten-year knot. Jiang Longcheng sincerely apologizes to his daughter-in-law.
Jiang Shixue’s attitude changes from disdain to dependence, and romantic feelings grow in their bickering daily life. Lin Feng’s hidden dragon identity remains concealed.
