What's the most terrifying thing in the world? It's not ghosts. It's not demons. But rather finding out that the people living around you have been secretly replaced. The appearance and manner of the TA is exactly the same as the person you are familiar with, but only you know that there is an unknown monster hidden within that human body. Chen Heng realises that his mother is really not her. He alone confronts with the terror, but discovers the more shocking and dreadful other side of the world, hidden within the everyday life.