Shadow Divers: The True Adventure of Two Americans Who Risked Everything to Solve One of the Last Mysteries of World War II

by Robert Kurson

A great diver learns to stand down his emotions. At the moment he becomes lost or blinded or tangled or trapped, that instant when millions of years of evolution demand fight or flight and narcosis carves order from his brain, he dials down his fear and contracts into the moment until his breathing slows and his narcosis lightens and his reason returns. In this way he overcomes his humanness and becomes something else. In this way, liberated from instincts, he becomes a freak of nature.

The things that separates the great from the adequate equates to lifespan in a dangerous sport, just like alpinism. Thing is, accidents can come for all.