Once a year, thousands of sharks travel great distances to the frigid waters of Alaska.

The sharks make the journey for a predestined encounter... with the Pacific salmon... The salmon make their own heroic odyssey...to spawn in their home waters...to create the next generation...

But first, they must outrun the explosive salmon shark – Alaska’s icy killer. It is a David and Goliath battle – when these two great migrations collide in one of Nature’s great spectacles.