Sam came across dissociative identity order by accident.  Until he began researching his topic, he had never heard of it before. It is an illness that can come at anytime, any place that overtakes your sense of reason and memory  "What’s scary, "Sam writes, "is that some patients with DID can look into the mirror and don’t even recognize who they are anymore."  Here, he writes of unforgettable football legend Herschel Walker – unforgettable to us.