National Geographic Explorer Bertie Gregory and his team are in Zambia, Africa, trying to film one rare moment when a pride of lions takes on one of their most formidable foes – the mighty cape buffalo.

National Geographic Explorer Bertie Gregory leads a team across the infamous Drake Passage, one of the world's most dangerous stretches of ocean, to the remote and windswept Elephant Island. His mission: to find and film one of nature's greatest wildlife spectacles, a feeding aggregation involving hundreds of gigantic fin whales, the second largest animal ever to have lived.