The World's Most Extraordinary People

Researchers encounter a girl whose heart has formed outside her rib cage, a man who can spend nine minutes underwater without taking a breath and a woman who is growing a second skeleton.

The human body has an amazing capacity for survival. Researchers meet a man who injects himself with deadly snake venom and another who is the only person in the world to be completely cured of HIV.

In some of the most extraordinary medical cases ever, researchers meet a man who feels no pain, a woman who can smell Parkinson's disease and a head-injury survivor who can suddenly play the piano.

Researchers encounter a girl with two hearts, a man who can sing two notes at once, a woman who can bend in amazing ways, a girl who is allergic to everything and a man who can run 350 miles without stopping.

Researchers meet a man with bones as strong as granite, a woman who became pregnant with twins in two separate wombs, a girl whose arm won't stop growing and a woman who gets lost in her own home.

Researchers meet the engineer who fixed his own heart and a man who can taste words. They also encounter a man who has multiple sclerosis but can now cycle and scuba-dive thanks to a new treatment that has reversed his disease.