This series is the first large-scale production TV drama with a frontier defense theme in Guangdong Province since the founding of the People's Republic of China. The series is based on the law enforcement duties of the Guangdong Province frontier defense officers. The main storyline revolves around the life-and-death struggle between the frontier defense officers, who fight in the south gate of our motherland during the peaceful era, and the smuggling criminal groups. It passionately praises the frontier defense heroes of our time who protect the borders and coastal areas. In the dead of night at the Chinese border, the public security frontier defense detachment of Jianghai City discovered smuggling goods worth hundreds of millions yuan aboard the smuggling ship "Sea Snail". However, the valuable cargo disappeared after a fierce gun battle at sea. The public security frontier defense detachment commander Yan Le-hui was appointed to investigate the truth behind the case, thus beginning a secret reconnaissance.%