Shen Cong transmigrates into the body of Di Renjie's own nephew.
He knows all twelve Bone-Piercing Spikes, can scale walls several zhang high with the Startling Swan Step, and can recite the entire series plot backwards.
The Embassy's Terror, The Blue Robe Mystery, The Bloody Eagle... He remembers every case, every dead end, and every person who was supposed to survive, all crystal clear.
Di Renjie thinks Shen Cong is just a young man who has studied for a few years,
never realizing he carries twelve iron spikes at his waist and has secretly trained in lightness skills for three years, waiting for the crucial moment when he can take the fatal blow meant for him.