This 2-hour special crisscrosses billions of years of time and space to show how everyone, and everything, is linked in one universal story. It weaves together science and history to reveal how an epic series of improbable events connect.

For four billion years, volcanoes have impacted life on earth. Empires have been destroyed and civilizations decimated. We'll travel to volcanic spots around the world made infamous in history.

Earthquakes have ripped through the planet's surface ever since it was born, and throughout history, mankind could do little to counter their seismic impact.

We'll look at cutting-edge systems that attempt to measure the unmeasurable.

An avalanche can stretch a mile wide, weigh more than a million tons, and accelerate to 80 miles per hour in five seconds. Though majestic and beautiful, the avalanche is the only natural disaster almost always caused by its victims.

As temperatures rise, a global meltdown has begun. From the Andes to the Himalayas to the Alps, glaciers are vanishing. In Antarctica and Greenland, vast ice sheets are turning into liquid.

This 2-hour special crisscrosses billions of years of time and space to show how everyone, and everything, is linked in one universal story. It weaves together science and history to reveal how an epic series of improbable events connect.

For four billion years, volcanoes have impacted life on earth. Empires have been destroyed and civilizations decimated. We'll travel to volcanic spots around the world made infamous in history.

Earthquakes have ripped through the planet's surface ever since it was born, and throughout history, mankind could do little to counter their seismic impact.

We'll look at cutting-edge systems that attempt to measure the unmeasurable.

An avalanche can stretch a mile wide, weigh more than a million tons, and accelerate to 80 miles per hour in five seconds. Though majestic and beautiful, the avalanche is the only natural disaster almost always caused by its victims.

As temperatures rise, a global meltdown has begun. From the Andes to the Himalayas to the Alps, glaciers are vanishing. In Antarctica and Greenland, vast ice sheets are turning into liquid.

This 2-hour special crisscrosses billions of years of time and space to show how everyone, and everything, is linked in one universal story. It weaves together science and history to reveal how an epic series of improbable events connect.

For four billion years, volcanoes have impacted life on earth. Empires have been destroyed and civilizations decimated. We'll travel to volcanic spots around the world made infamous in history.

Earthquakes have ripped through the planet's surface ever since it was born, and throughout history, mankind could do little to counter their seismic impact.

We'll look at cutting-edge systems that attempt to measure the unmeasurable.

An avalanche can stretch a mile wide, weigh more than a million tons, and accelerate to 80 miles per hour in five seconds. Though majestic and beautiful, the avalanche is the only natural disaster almost always caused by its victims.

As temperatures rise, a global meltdown has begun. From the Andes to the Himalayas to the Alps, glaciers are vanishing. In Antarctica and Greenland, vast ice sheets are turning into liquid.