Mysteries Unearthed With Danny Trejo

History's biggest discoveries aren't always its best.

Some discoveries come with consequences; gold that ruins lives, a cursed wreck beneath the sea, and a hidden safe linked to a famous burglar, show how the past can be as dangerous as it is tempting.

From a live WWII bomb discovered decades later, to a Civil War cigar hiding secret orders, to a Viking sword unearthed by a child, these finds reveal how the remnants of war can resurface when least expected.

From a $4 flea market frame concealing the Declaration of Independence, or a lost Fabergé egg in a Midwest flea market, and even the holy grail of comic books hiding in someone's wall, we revisit the most astonishing, valuable discoveries.

Heavy-metal marvels prove history's strongest secrets can't stay buried.

A species thought lost forever is spotted again; a dog plays an unexpected role in recovering the World Cup trophy; a puppy from the Ice Age emerges intact after 18,000 years; revealing just how unpredictable the natural world can be.