2. Birth of Shadow Ops

Retired members of FOG, the Field Operation Group launched in secret by President Carter, detail their covert mission to rescue 52 Americans taken hostage by Iranian forces in 1979.

3. Forged in Slavery

The unearthing of burial grounds for enslaved people at an old ironworks leads archaeologist Whitney Battle-Baptiste on a journey into the history of industrial slavery in the United States.

4. The Black Wild West

Historians chronicle the untold stories of Black settlers who journeyed to the Wild West in search of freedom and opportunity, examining their roles as marshals, cowboys, soldiers and more.

5. CIA's Museum Declassified

The CIA Museum opens its doors and vaults to reveal the top secret stories behind agency documents, "Argo" artifacts, a Soviet helicopter used in the hunt for Osama bin Laden and more.

6. Lost Airship

Experts delve into the undelivered promise of rigid airships on the American military landscape, and the tragic fate of the USS Macon and efforts to explore its remains in the Pacific Ocean.