New York City's Central Park is the focus. Included: its natural and engineered components; its most secret spots; and the meaning of the codes on its lampposts. Also: the history of a village that disappeared from the area.
The Hollywood Walk of Fame stars on Hollywood Boulevard are spotlighted, including a look at how they're manufactured. Also: secrets surrounding Grauman's Chinese Theater; and the security surrounding the iconic Hollywood sign.
Secrets of Grand Central Terminal in New York City are explored. Included: rumors of a secret track; a foiled Nazi plot to access the basement. Also: a look at the Tiffany glass used in the face of the station's large clock.
Possible hidden messages at the Lincoln Memorial are investigated. Also: details on Abraham Lincoln's secret travels around Washington, D.C.; and a visit to a little-known cottage where Lincoln spent part of his presidency.