In a future not so very far away, miniaturized human workers represent a breakthrough in medical science. This intrepid corps of caretakers acts as a workforce designed to be an essential part of any health care regime. Intronauts are personal cleaners, injected into the human body to carry out essential maintenance in order to keep a level of health and hygiene beyond compare. But what happens if your cleaner discovers your dirty laundry? And how much do you actually want to know about what goes on deep inside your body?