The Strange Case of Dr. Kappler : The Doctor Who Became a Killer

In 1975, Dr. John Kappler secretly attempted to kill three of his patients.

Ten years later, when he tried again, he was arrested, but freed on a technicality.

Then, in 1990, Kappler deliberately ran down and killed two absolute strangers.

Here is a chilling portrait of a doctor gone wrong--and a medical establishment that looked the other way.