From virtually the moment we're born, there's a story that's preached across cultures and continents. It's a familiar fairy tale, that finding one true love is the key to a fulfilled and happy life. As an adult, we're forced to reconcile the messaging on monogamy with one simple fact: humans are terrible at it.
What do biology, human history and the promiscuity of bonobos reveal about monogamy? Experts and everyday couples weigh in on shifting cultural norms.

Does the stock market accurately reflect the status of the economy? Finance specialists discuss market history, valuations and CEO incentives.

A heroic congressman, Leo Joseph Ryan Jr, travels to Jonestown; some Temple members plot their escape. Jim Jones realizes the walls are closing in and plans his final stand. After the massacre, the world learns about mass murder/suicide in Jonestown, orchestrated by cult leader. Survivors try to piece their lives back together.

Sultan Mehmed II's siege of Constantinople enters its third week. Mehmed's artillery teams continue their relentless bombardment of Constantinople's walls. After his navy suffers a devastating defeat, Mehmed moves his ships overland to the Golden Horn in a daring, visionary feat. In the shadow of betrayal, Giustiniani attacks the Ottoman fleet.

The nervous system is fundamentally electric. When we move our arm, it moves because a electric signal has been sent to the muscle that controls it. Now, because the brain is electric, we could also use electricity to record what the brain is doing or bypass it entirely, and control a body. That means that we could restore movement to people who are paralyzed, feel through an artificial hand as if it was our own, and even read people's minds.
Michael Stevens explores how electricity can be used to move cockroaches, control other peoples' limbs and even read peoples' thoughts.

Millions of tourists photograph the ancient monuments of Rome every year. But is there more to them than people guess? There's new evidence that these ruins were once machines, designed by Rome's emperors to connect their power with the sun. Did Roman emperors harness the power of the universe to awe and terrify the people of Rome? We uncover the last, great mysteries of the ancient world's greatest empire.