WASHINGTON: An epic documentary comes with some epic inconveniences. Like living in a dark cave for days on end, trying not to lose your mind. Or taking two hours to get a glass of water, which will freeze if not immediately stored in a Thermos.

Or just being really, really cold and really, really stinky — personal hygiene hindered by teeth-chattering conditions — for a seriously long time.

That’s just a slice of the little sacrifices involved in making “Planet Earth,” a joint project of the BBC and the Discovery Channel that takes viewers on an 11-hour adventure around the world, from the deepest caverns in Mexico to the highest waterfall on Earth.

Along the way, the intrepid group of filmmakers — whose logistical challenges merit their own telling — captured images of flora and fauna never before recorded.

“It’s remote, it’s uncomfortable, you have to go through those things to get something new, exciting,” says cameraman Jonny Keeling, who shot footage of gazelles in Mongolia and wolves chasing caribous. “So you use that to challenge yourself. And honestly, that, for me, is the enjoyment of the job. But it is the kind of enjoyment that sounds slightly perverse, isn’t it?”

Perverse? How about living in an old, hut-like construction container in sub-zero temperatures for seven months? That’s what the two-person team who documented the life cycle of emperor penguins endured in Antarctica to get snippets of film history.

With no contact with other humans for weeks at a time, the twosome kept themselves sane with an iPod, some books and a yoga mat.

“Planet Earth” — Discovery’s most ambitious project, with each installment costing upward of $1 million — is a follow-up to the BBC’s enormously popular oceanic series, 2002’s “Blue Planet.”

In Antarctica, Fairley and Olivier’s hut had no insulation, so they survived by constantly wearing what Fairley calls “voluminous puffy-down clothing.” “Overall, we did very well and were very content in our little working-living space,” Fairley wrote. —Dawn/The Washington Post News Service