This is one of the best mysteries that I have ever read. It was so suspenseful that I let the last 30 pages drag out for 3 days; only reading 10 pages a day because I didn't want it to end. The plot is simple. U.S. Marshall Teddy Daniels and his new partner, Chuck Aule, ferry to Shutter Island to investigate the disappearance of an inmate of Ashecliffe Hospital for the Criminally Insane. The mystery is how could a female patient held in a cell that is no bigger than a closet, manage to escape out of a locked cell, past several locked and manned checkpoints, then flee a rat-filled island that is surrounded by pounding waves and 50 degree water. Something strange is taking place on the island. The government funded hospital should be able to easily house more than 500 patients, yet there are less than a hundred incarcerated. There are almost three times as many staff and guards on the island than inmates. The head doctor could be a former Nazi. Rumors of illegal surgeries are hinted. The time is the early 1950's when hallucinogens were first being introduced into psychiatric treatment. This novel was optioned to Hollywood and Martin Scorsese directed the film that stars Leonardo DiCaprio. It's supposed to open in early October. The film adaptation will be tricky to pull off since this book is not bound to basic laws of physics. Visualization of the intricate character studies might be compromised. I recommend reading this book first if you are planning to view the film.