Off the coast of San Francisco, an unexpected killing challenged the great white shark's supremacy as the ultimate predator when one became prey to a killer whale. Whale-watchers witnessed a stunning act of nature as a killer whale rose to the water's surface with a great white in its mouth and held it there for 15 minutes. Even more amazing, biologist Peter Pyle was nearby and able to get underwater footage of two whales feeding on the shark. They ate the liver and then departed the scene, leaving the rest to the birds. The incident raised questions, such as how did the killer whale take the huge shark without a struggle? And why did the whales only eat the shark's liver?