Chen Mo, a researcher in a national classified department, saw his wife Lin Wan die in a car accident three months ago. One day, wearing the Bluetooth earphones left behind by his wife, he actually heard a strange man ask, The fact that you are still alive has not been exposed, has it? Subsequently, his five-year-old son inadvertently recited the top-secret key of the Abyss Project, insisting that he heard his mother's voice at home. Following up on abnormal electricity bills, midnight noises, and moved documents, Chen Mo discovered a secret space hidden under the study floor. It turned out that Lin Wan was not an orphan, but an overseas spy, and her parents and foreign husband had been hiding underground all along. Facing the theft trojan and the silencing plan, Chen Mo endured the pain of betrayal and wiped out the entire spy group in one fell swoop.