The next morning, Gu discovers that the worms have been raised with herbs that alter the worms' genes. The herbs make the worms eat the same food as they did before, which makes them unable to distinguish between different kinds of food. When they eat the food, they harm the brain and drive people crazy. The next day, Gu finds that he has only half of the research he had planned to complete. He thanks Gu for his help, and he plans to use the herbs to make a drug that will help people who are immune to the worms