What is madness?  Where does it come from? And what happens when it's present in multiple siblings?  These are the operating questions in this well researched story about the Genain quadruplets (not to be confused with the Dionne quintuplets). This account is also a deep dive into the standard of care for mental health and the workings of the National Institute of Mental Health in the 1960s. The story is creepy, revealing, and mesmerizing.