In the future city "Forgotten City" where memories can be stripped, traded and stored, Lin Mo is a "blank man" - he voluntarily erased his entire past. However, a recurring dream about a lighthouse haunts his empty soul like a ghost. In order to find out the truth of the dream, he found the mysterious memory restorer Xiao Lan. As the memory fragments were pieced together piece by piece, they not only revealed Lin Mo's astonishing identity, but also touched upon a conspiracy behind the "Yongyi Group" that controls the city that could subvert the world. The truth he pursues may be heavier and more dangerous than the past he chooses to forget.