Researchers begina slow and cumbersome descent, deep into the Grootboom Cave, hindered by head-to-toe protective suits, but those suits are the only things standing between safety and exposure. Thousands of bats live inside this cave, and not far from the cave's entrance is the city of Johannesburg, South Africa, a heavily populated area. Any number of these bats could potentially be carrying a deadly pathogen. Known as zoonotic, these are diseases...

In this wordless time-travel adventure, three children at a Passover seder visit ancient Egypt to help baby Moses find his way safely to Pharaoh's daughter. When a family settles at the table for Passover, their dog nabs the afikomen bag (containing matzah used for the seder) and dives under the tablecloth. The children follow him and find themselves transported to ancient Egypt. There, they see baby Moses' mother and sister Miriam placing him in...

Getting back was only the beginning as the most spectacular time travel adventure ever continues in part II, the sequel that proves that lightning can strike twice. Marty and Doc launch themselves to the year 2015 to fine tune the future.

-- Into the Wild Immediately after graduating from college in 1991, McCandless had roamed through the West and Southwest on a vision quest like those made by his heroes Jack London and John Muir. In the Mojave Desert he abandoned his car, stripped it of its license plates, and burned all of his cash. He would give himself a new name, Alexander Supertramp, and, unencumbered by money and belongings, he would be free to wallow in the raw, unfiltered...

Hard as it is to swallow, cutting-edge theories are suggesting that our universe may not be the only universe. Instead, it may be just one of an infinite number of worlds that make up the multiverse. In this show, Brian Greene takes us on a tour of this brave new theory at the frontier of physics, explaining why scientists believe it's true and showing what some of these alternate realities might be like. Some universes may be almost indistinguishable...