The human body is a resilient, versatile and adaptable machine, but it's evolved to operate at an optimum weight. How, with two thirds of the United States either overweight or obese, are we are pushing our bodies to their natural limit?

Extreme Bodies reveals the extraordinary stories of the most unique people on the planet. Conjoined Twins explores the amazing structures of people who are literally one in a billion!

Harnessing some of the most sophisticated medical imaging systems on the planet, Extreme Bodies takes us on a journey deep beneath the skin of the tallest giants in America: men and women who are often suffering from life-threatening conditions.

Shaped by genetic anomalies buried in their DNA, dwarfs' bodies are the products of incredible anatomical engineering. With the aid of cutting edge scanning techniques, Extreme Bodies uncovers the science hidden within the world's smallest people.

Witness the destructive power of water, when floods strike without warning. See it all up-close - from the overwhelming storm surge of Hurricane Katrina, to the destructive landslides in Venezuela, to the Mississippi River floods.

See the deadliest volcanoes on the planet. Special effects take you inside some of the world's most famous eruptions. With spectacular new footage of lava rivers, superheated flying rocks, torrents of boiling ash and lethal mudflows.

Witness the beauty and destruction of the biggest light show on Earth. State of the art high-speed cameras capture lightning for the first time, on a journey from the US to Venezuela and equatorial Africa.

Witness the devastating power of an avalanche, from cameras placed directly in the path of descending snow. Stunning special effects recreate the unimaginable horror of the worst avalanche disaster in US history.

Take a journey into the heart of the planet's most furious snowstorms, and feel what it's like to try to survive the sub-freezing temperatures, howling winds, and blinding snowfalls.

Every trip on the Earth's oceans is a potential battle with nature. Witness the awesome forces that can punch a giant hole in a supertanker, capsize any size ship, and leave you fighting for your life on the open seas, thousands of miles from help.

Witness the awesome beauty and power of these amazing storms. See the most spectacular footage of twisters ever shot, along with the stories of people whose lives have changed forever after encountering these mega-storms.

Experience the dramatic power and destructive potential of the largest storms on Earth.

Hawking and his team examine inventions that will change how humans deal with crises in the future, including a Boston Dynamics' LS3 and Atlas, Gecko Skin Adhesion, and Pathogen Scanner..

Hawking and his team examine inventions that will change how humans deal with crises in the future, including a KMAX, Robo Sally, and Tracking Point Rifle.

Hawking and his team examine inventions that will change how humans deal with crises in the future, including a virtual reality SWAT training, bio printed live tissue, and oculus rift.

Hawking and his team examine inventions that will change how humans deal with crises in the future, including a pavegen, automatic warehouse, and digital avatar.