Host Mo Rocca shows us what device is keeping sharks away from swimmers; the video doorbell connected to your smartphone; the history of the DC-3 airliner; and the coating for plastic bottles that gets the last drop.

Host Mo Rocca shows us the physics behind the tallest roller coaster; making makeup at home with the inventor of the 3-D makeup printer; historic arcade and video games; and the headlights for your running shoes.