I Am a Practicing Lawyer Who Specializes in Litigating Unjust Cases in the Underworld.

Lin Yan is a lawyer during the day and a yin and yang agent at night. The "yin and yang seal" under his collarbone is a certificate for traveling between the two worlds. Use it every time and then use it less until it disappears completely. Metro Line 7 derailed, killing seven people. The female ghost Su Wan came to the door and accused her boyfriend Chen Mo of causing the accident. Lin Yan traced and found that the real culprit was the parasitic supernatural entity "Iron Claw" in orbit, and Chen Mo exchanged his soul for three more seconds for Su Wan to live. Su Wan stayed in the earthly world from then on and refused to leave. This is just the beginning. Thirty years ago, a "two-way exchange" channel in the Yin Division Communications Bureau was privately modified. Yin De could be exchanged for RMB, which involved six soul contracts that were remembered by a wall. Lin Yan's father, Lin Yuanshan, discovered the truth and tried to close the passage, but was trapped in a crack behind the wall for seven years. He handwritten twenty-two volumes of "Yin Law Jurisprudence" in the cracks, leaving the following instructions: three copper bells, a wall, and contracts between six people. There are twenty cases, each of which is an independent dispute in the earthly world - the old lady who left a will to a cat, the cram school student who sent a message after his death, the anchor who rewarded people with ghost coins - but each case is a clue, pointing to the same wall. Chen Nian, Bai Chongyuan, Zhang Youfu, Qian Min... The names of the six people from the first maintenance team thirty years ago appeared one by one. Lin Yan fought lawsuits during the day and collected copper bells and terminated the contract at night. Someone inside the wall has been waiting for seven years, and someone outside the wall has written twenty-two volumes of jurisprudence, waiting for another pair of hands to take it over. Twenty cases are over, the wall is opened, and people come out. The yin and yang seal disappears. On the title page of Volume 23, Lin Yan signed his name. The whole book itself is the "Collection of Yin Law Jurisprudence".