Moss Town is a southern town surrounded by mountains. It is named after the year-round rain and the stone roads covered with moss. The century-old clock tower in the center of the town is a landmark and the town's "memory container" - the clockkeepers of the past generations hold the secrets of the town, including underground party files from the Republic of China, secret transactions in special years, and "ledgers" that can subvert the peace of the town. The protagonist Lin Shen returns to his hometown after the death of his grandmother (the last clockkeeper) and is forced to get involved in the fight over the "ledger" while uncovering the complicated past of his family and the town.