Decades ago, Ni Zhengang volunteered to work for the development of the countryside of a tier three city when he was young. After retirement he returned to the big city. Although his wife always wanted to go back to visit, for years he refused to go. Living in his own small world, his bad temperament lead him to act strangely, creating an image of a misfit outsider.After the death of his wife, the conflicts between Ni Zhengang and the people around him deepened: When young people in the Community wanted to take over the elderly's leisure space to play basketball, he would not stand; when the Neighborhood Committee repeatedly urged him to go to the police station to deregister his wife's residence, he resisted; After going on a matchmaking TV show and meeting different blind dates, he liked none; Knowing a peer was sent to a nursing home, he went over to rescue her but failed when he discovered that peer preferred life in the nursing home, breaking his stereotype; His relationship with his son and daughter-in-law became fraught because of the unavoidable transfer of the ownership of his house.Xu Wannian, Ni Zhengang's good friend, unexpectedly fell into a coma perhaps due to a brain tumor. Xu Wannian, like Ni Zhengang's departed wife, has always wanted to return to the tier three city. In order to not only fulfill the will of both his departed wife and his friend's, and also to avoid the harassment from the Director of the Neighborhood Committee, Ni Zhengang set his mind, ready to face the secret hidden deep down in his heart for many years.Ni Zhengang decided to take Xu Wannian, who was then hospitalized, to go on a trip back to the tier three city. They fled at night, Xu Wannian rode a motorcycle combination on the highway with Ni Zhengang in the sidecar, the two enjoyed the beautiful landscapes and a carefree time. However the motorcycle got a flat tire before long, the two had to ask Ni Jianguo, Ni Zhengang's son, to come to rescue. One day after returning home, when Jianguo was not home, the two stole Ni Jianguo's car key and ran away again, this time, the two successfully drove to a small town in the neighboring province.On that night, Xu Wannian took Ni Zhengang to a Massage Parlor to experience life. When they sat down with the ladies, the two started giving them lessons, persuading the girls to start a new life. However, the drug and gang enforcement broke in, mistook them for clients and took them back to the local police station. Ni Jianguo again went to the small town overnight to rescue his father. On the contrary, the police station director told Ni Jianguo that he should be proud of his father. By the time Ni Jianguo took Ni Zhengang and Xu Wannian home, the two secretly went away, again for the third time, to the train station, leaving Ni Jianguo a mysterious envelope inside which were a hand-written letter and a bank card.Ni Zhengang and Xu Wannian boarded the train to the tier three city, where they had worked in their youth. In the meantime, unbeknownst to them, they had become web celebrities - the "Hard Core Grandpas" - because of their heroic misbehavior. which they had no idea of. When the police appeared on the train for routine inspection, a strange man put a backpack into the hands of Ni Zhengang, which the police found was filled with prohibited items, soon it was proved that the strange man was to suspect. Then the police noticed Ni Zhengang's bag, requesting to check. But Ni Zhengang refused to cooperate, causing him to be handcuffed by the police. Ultimately, the bag contained nothing more suspicious than a cat and the police liberated Ni Zhengang with wry smiles. Just as the police were about to leave, Ni Zhengang stopped them, and identified a child trafficking suspect. With the cooperation of Xu Wannian, the criminal was subdued successfully. Ni Zhengang and Xu Wannian became heroes on the Internet again.