Jiang Zhaoying, the daughter of a convicted official, brandishes a marriage contract right before her execution. She is forced to enter a hundred-day cooperative marriage with the powerful official Xie Chenzhou. Together, they team up to crack the incriminating evidence hidden within paper and ink, investigating the disaster relief silver robbery case from six years ago. Along the way, the two test each other, achieve mutual redemption, and ferret out the Duke of Ningguo and the eunuch faction. Relying on her talent in identifying paper and examining ink, Jiang Zhaoying establishes the Paper Evidence Bureau independently without relying on anyone, standing equally and protecting each other with Xie Chenzhou, who has laid down his military power, using a single piece of clarity to prove the innocence of the world.