For thousands of years, the dreams and visions of the dying have captivated cultures. But what causes them? And are they real?

Florida college student Lindsey Meyer and Michigan E.M.T Kevin Nesbit both come down with a painful sore throat. What seems like a symptom of the common cold, soon spirals into a life or death situation.

Paul and Alison Frase were told their child's disorder had no treatment and no cure. Scientists tell them their one hope depends on finding a dog and the right genetic code – they set out on a quest to find that one-in-a-million dog.

Dr. Bill Lidner collapses just hours after returning home from a family trip overseas. His young daughters find him bleeding on the stairs of their Ohio home. They didn't know it then, but it is the first sign that something is very wrong.

What do California honeymooners, a surfer in Hawaii and a toddler in Tennessee have in common? That's what several doctors and the CDC in Atlanta spent months trying to figure out.

High school volleyball player Jeanna Giese complains she's fatigued and has numbness in her arm; then, she starts experiencing double-vision and loss of balance, making it clear she is suffering from something far more sinister than a sports injury.