Some archeological finds are so baffling, they challenge what is known about the past; learning the truth about these mysterious ruins and answering the questions they continue to present.

More than 80% of the Earth's oceans remain unexplored, and in many ways, the underwater world is the final frontier; as new technology allows people to explore oceans and deep lakes more than ever before, nobody knows what they will find.

The animal kingdom is full of deadly predators, and some of them attack in extraordinary and inexplicable ways; some animals strike back at humans for reasons beyond normal defense and hunger.