How does magic achieve the trick of changing people? The model went into the box and was covered with black cloth, but it disappeared. After a while, the black cloth unveiled the model and solved it. I watched it at the scene. No, it's a 37-degree body separation method. This is a difficult magic, and the angle must be kept at 37 degrees. Then the people inside will go out from another box, which is completely unknown to the outside audience and extremely fast, so it is impossible to see clearly. Using a black cloth gives people a sense of visual ambiguity, so most people will pay attention to it and will not take into account the overall situation.