One day, one woman came into the ER(emergency hospital) and said she was very ill, but Maxine, who was the doctor there, couldn't find why she was sick, and soon after, she was died. Before she died, she said she took a pill, but Maxine didn't understand what it meant. However, they discovered that she died of tetrodotoxin. Maxine started to investigate it as an murder to find out who killed her. But, she also began to involved in this case. There come many people in this book, doctors, researchers and detective, and almost all of them were Maxine's friend. But, there is the murderer among them. You couldn't expect who is the murderer.It was like solving clue. I 'm sure that not only those who like mystery, but also others will like this story.