Lin Yan was involved in the whirlpool of the business world due to the death of his family. A pair of hands that can settle the world's accounts, but in the mud, he grasped the abacus that changed his destiny. When the Wang family used fake silver to defraud the rice shop, he borrowed the money from Shen Zhiyi, the legitimate daughter of the Shen family. He tore open the loopholes in the account book with his own hands, and used bead rope to tie up the conspiracy of the powerful in the rain; when the smuggling of salt at the wharf involved a hidden stake in the Shanhai Alliance, he cracked the secret account with his mental arithmetic, and let the sound of abacus become a sharp blade to pierce the fog of the business world. He is a "poor man" who has been stepped into the mud, and a "living abacus" that scares the Jiangnan Business Alliance: he uses the nine-return division method to expose the fake silver conspiracy, uses secret accounting books to overturn the shady secrets of smuggling, and even turns "abacuses" into the key to the government and businessmen on the chessboard of the powerful. From the small abacus in the streets to the big picture of controlling rice, salt and iron, he worked step by step without changing his original intention - the blood bubbles in the palms are the price of all the people's hearts, and the unstained clarity between the brows is the ruler of the business road more expensive than gold. "Secret Code of Business", Lin Yan understood that the most exquisite algorithm in the world was never a numbers game - it was to sort out the greedy gaps of the powerful, and to guard the conscience of poor families. It also made those who had stepped on him into the dust eventually hear the word "Lin Yan", like a bead falling to the ground, the sound was deafening on Shanghai Long Street. The way of business is like a chess game, counting thousands of waves; the human heart is like a scale, measuring thousands of mountains. A young man from a humble background used an old abacus as a blade to carve out a counterattack from a poor family to a noble family in the ancient business world where power and interests were intertwined - do you think he was counting money? No, what he calculated was the justice that this world should have.