There is hunger in the forest at night.
A wild cry is heard beyond the trees as darkness falls. It is the witching hour of stealth and surprise, when wolf packs hunt their prey. Fear grows in the wind as the moon reaches its full ascent.
Using a natural calculus of speed and distance, wolves drive their quarry deep into the snow. Livestock are vulnerable in the trappings of ice, where the wolves show their famed killing prowess. The chases end with an assault of teeth and snarls.
Learning what's beyond the menace is not for the faint of heart. But Shaun Ellis and his girlfriend Helen Jeffs are willing to risk their lives and leave behind the last remnants of a human existence to survive in the world of the wolf.
"It's almost like the wolf brings out a subconscious in you, a way of dealing with the world," Ellis said.
But to do so, Ellis and Jeffs have to become wolves themselves.
"Lose your human, think wolf," Ellis said to Jeffs.
It is a skill he has honed in the last few decades. He has done what many scientists thought impossible and has become an accepted member of a captive wolf pack.
"This is the way that you need to study these animals. Get close to their world. And then they will share their secrets," he said.
Ellis is a careful listener, both to their secrets and their warnings.
"In the beginning, the warnings were very, very scary. It was the animal trying to teach me about its world," Ellis said.
As a man living among wolves, Ellis bade farewell to the comforts of human society and took his place on the ground to learn the ways of a canine hierarchy.
"When nature turns off her lights, we don't have any luxury, and that's when you have to really start to come into your own and understand the wolf," Ellis said.
He created his own sanctuary to study captive wolf behavior at the Coombe Martin Wildlife Park, on England's southwest coast. His goal is to find ways for wolves to peacefully co-exist with ranchers whose cattle are susceptible to attack.
"I've seen wolves able to short out an electric fence by laying objects between the two wires. They're entirely highly intelligent animals that will breach most problems," Ellis said.
To know the wolves' minds, he first had to learn their sounds. He became fluent in a complex language of snarls, whimpers and howls, one where the subtleties of translation could get Ellis seriously injured simply by missing a cue.
"In my time I've picked up a few accidental bites where two wolves -- wolves either side of me -- have snapped," he said.
But even with the threat of violence, there are surprises. Ellis is the first to say he has fallen for the dark magic of wolves.
"Very quickly they could smell something in the wound that maybe doctors or we as people couldn't clinically clean. So all that would happen is that the wolves would just pluck out the stitches, very gently with their front incisors, and just thoroughly lick inside. And clean it thoroughly, so much so that it would heal in a fraction of the time," he said.
As the secrets of the natural world began to reveal themselves, Ellis learned that it would not be an easy transition from his wolf identity back into human society.
"When you leave here and you go back and try and join society your emotion doesn't come out with you," he said.