Sharks have been worshipped by ancient civilizations, reviled by seafarers, consumed by gourmets and studied by marine biologists. Their powerful, streamlined bodies inspire ship and submarine designers, and their immune system may help in fighting diseases. Yet, it is their formidable jaws and teeth that invoke fear that turns any shark attack into frontpage news. This exploration of findings from research groups worldwide reveals sharks to be much more than just mindless, killing machines. It shows how sharks are the product of over 450 million years of evolution, honed to perfection as some of the sea's most sophistiated predators.