Huang Dan is a construction engineer. He has no father and no mother. He has lived with the housekeeper since he was a child. His pain nerves are naturally different from ordinary people, and he lacks the emotion of smiling. He can only simulate it through reference objects. This is his secret. A magical The experience made him start his inexplicable time-traveling journey. The theme of the story is mainly time-traveling, telling about Huang Dan encountering complicated people and things in different worlds. While completing the task, he also realized what kind of emotion it is to laugh. The whole narrative is smooth, the plot is compact, interlocking, the overall style is more realistic, and the interests, survival, and emotions between people are vividly interpreted, and it is worth reading.