Satellite images capture a large compound of abandoned structures overgrown with vegetation in Clark County, Indiana. Experts investigate and uncover the Indiana Ordnance Works, a derelict WWII munitions factory that played a crucial role in US military history, producing smokeless gunpowder. In 1964, its name changed to the Indiana Army Ammunition Plant.

Satellite images capture a mysterious fortification concealed beneath a patch of woodland in the remote stretches of Norfolk, England. Experts investigate rival royal families and Gresham Castle, a lost castle destroyed during a medieval blood feud.