“I grew up watching footage of Nile crocodiles flying out of the water, eating zebras and wildebeest. And the thought of getting in the water with one was completely incomprehensible to me — just impossible.”

Those are the words of photographer Roger Horrocks, who has compiled some close-up underwater images and video of – wait for it – Nile crocodiles.

Check out this close encounter Horrocks had with two Nile crocodiles.

In 2007 the South African native gave up a decade-long career in corporate law to focus on environmental photography. Since then, Horrocks has swum with large predators including bull sharks, great whites and now, Nile crocodiles — one of the few animals that regularly prey on humans.

Over a nearly two-year period beginning in 2009, Horrocks and fellow photographer Didier Noirot dove with Nile crocodiles in Botswana’s Okavango Delta. When the water rises in the Okavango Delta, massive papyrus beds can float to the surface; under water, their roots create virtual caves where the crocodiles drag their prey to decompose for later feedings.

Tailing a crocodile deep into murky waters for the first time was “the most terrifying moment of my adult life,” Horrocks says.

“I was totally convinced that it was going to eat me,” he says. When you follow an animal into a cave, he says, “there is always a danger of it getting trapped or cornered.”

Horrocks and Noirots’ film, Into the Dragon’s Lair, aired on Animal Planet and BBC in 2010. Horrocks says his most gratifying experience while filming came during a 90-minute encounter with a crocodile that seemed relaxed and curious about their presence.

“I get a sense that our scientific view of crocodiles is perhaps limited,” says Horrocks. “These animals might be a lot more sentient and aware than we believe.”

As a follow-up project, the team has embarked on Touching the Dragon, which profiles a man in Costa Rica who has developed 20-year relationship with an American crocodile. Copyright 2011 National Public Radio. To see more, visit http://www.npr.org/.