Watch Holy Marvels with Dennis Quaid

From the strict, brutal codes of Hammurabi and the Samurai to the secretly malevolent evil eye and Voodoo dolls, history is full of remarkable stories of acts committed in the name of revenge. We uncover the dark forces that have driven individuals and nations to seek vengeance--often with deadly consequences.

There are some strongholds built to protect the sacred, like an impenetrable wall, an intimidating fortress, or a mystical river. But there are others used for more sinister purposes. In this episode, we uncover the remarkable stories behind some of the world's most imposing structures.

It's one of life's most confounding mysteries: What happens to us after we die? From heaven and hell to resurrection and reincarnation, we'll explore the remarkable possibilities of life after death.