From a revolutionary war era ship hiding under the streets of Manhattan, to a sprawling Roman villa unearthed in the backyard of an English home, or even an ancient Grecian maze long thought to be a myth--the strange structures uncovered in this episode sometimes lead to more questions than answers.

From priceless treasure found inside a lost city, to an ancient manuscript hidden behind a wall, explore mysterious secrets lost deep inside various unseen chambers, like tunnels, caves, or even burial sites.

From a deadly discovery hiding under one of America's most loved national parks, to a Nazi era weapon sunk off the coast of New Jersey, or even a blood thirsty predator found in Canada--you never know where a killer find is hiding or who may stumble upon it.

From a mythical monster that turns out to be real, to a deadly prehistoric animal, and a frozen tundra hiding a pandora's box full of lethal pathogens, these startling discoveries shock and terrify the world.

From a Chinese curse that turns out to be real, to human remains in a Founding Father's basement, or even a mysterious island in Central Asia with enough pathogens to kill the entire global population several times over.