The Secrets of Everything

Mysteries solved include what it takes to become the fastest man on Earth, why a boomerang comes back, and how bulletproof vests work.

Greg tests an urban myth about pennies and the Empire State Building, subjects himself to extreme cold temperatures and takes a hammer to his fingers, all in the name of science.

Greg tries to dig a hole to Australia, gets sucked into quicksand and discovers how fast you can get fat eating fast food. With a pig's help, he also finds out if it is physically possible to die of a broken heart.