In an ancient imperial court, Lu Tingfeng, a young man born with extraordinary hearing, is sent by his father to serve in the Jinyiwei's Secret Intelligence Division. Using his remarkable ability to hear through walls, he repeatedly cracks major corruption cases, foils conspiracies against court officials, and protects loyal ministers. Winning the emperor's favor, he eventually takes charge of the imperial intelligence service. Amid the turbulent power struggles at court, he remains true to his principles and moral convictions, gradually becoming a trusted confidant of the emperor.