In this clip from National Geographic's "Untamed Americas" series, a squirrel attempts to evade a hawk's talons. (National Geographic)

When cinematographer Neil Rettig and his veterinarian wife, Laura Johnson, returned to Wisconsin in 2014 after six months spent filming endangered Philippine eagles in the forests of Mindanao, friends kept sending them the link to a video they thought the couple would enjoy.

“You’ve got to look at this,” Laura remembers people saying. “It’s really awesome.”

It turned out that Neil was intimately familiar with the video — a hawk chasing a squirrel. After all, he shot it.

“It’s actually gone viral,” Neil said of the segment, taken from the 2012 National Geographic miniseries “Untamed Americas.”

And for good reason. The clip, lasting 3 minutes 31 seconds, is the squirrel world’s “Gone With the Wind,” its “Lawrence of Arabia” or “Saving Private Ryan.” It is a sweeping epic so beautifully photographed and masterfully edited that I doubt it will ever be equaled. As I kick off my fifth annual Squirrel Week, I want to celebrate this landmark piece of squirrel cinema.

The segment starts with an eastern gray squirrel foraging in fallen leaves. A red-tailed hawk looks down, then launches itself at its prey. More twists and turns than a Hollywood car chase follow.

The hawk plummets through a maze of branches!

The squirrel races up a tree and seeks refuge in its drey, then bails out a trapdoor as the hawk’s talons tear at the leaves!

The squirrel soars in super-slow motion from one tree to another!

I won’t tell you how the battle ends, except to say that today is the first day of Squirrel Week, not Hawk Week.

“Not all the drama has to happen out there in the wild with cougars and grizzly bears,” said “Untamed Americas” producer Karen Bass, a 25-year veteran of the BBC’s natural history unit. “We thought this was a pretty dramatic scene. What I liked about it was the idea of the relatability, that it could be happening right under your nose, and probably is if you live near a park or have a big yard.”

Others involved in the segment included producer James Byrne and field producer John Benam .

“In order to make that sequence, a lot of different elements had to stack up and fall into place,” Neil said.

Chief among them was a firm understanding of animal behavior. Hawk vs. squirrel took nearly two weeks to shoot and involved multiple squirrels and three hawks.

“You can’t get all those angles in one go, no way,” Neil said. “To me, the most important thing is to make sure everything is ethically good and that you’re biologically correct.”

The segment was shot in November 2010 on Neil and Laura’s 162-acre Wisconsin farm. Neil is a licensed falconer, which allowed him to get many intimate shots of his trained bird and other hawks. Sometimes, the bird was actually chasing a squirrel. Other times, it was filmed perching or flying, for shots that would be edited in to show detail.

For some footage, Neil was suspended in the forest canopy, sitting in a gondola attached to a guy-wire. It took weeks to acclimate a trained hawk to his presence up there.

Squirrels were filmed in extreme close-up — eyes blinking, whiskers twitching — and in super-slow motion, leaping among the trees. The most amazing shot may be a heroic jump captured against a stunning blue sky.

“We know the avenues squirrels take when going from Point A to Point B,” Neil said. That allowed the filmmakers to position a high-tech camera, called a Phantom, near one of these byways. It can capture action at 1,000 frames per second, revealing details not normally picked up.

“When the squirrel escapes into the hole, its tail is twirling around,” Neil said. “At normal speed, that would be the blink of an eye. With the Phantom, you can see detail. The hair is actually flying off the squirrel’s tail as it’s trying to stuff itself into the hole.”

Such encounters are life or death for the animals involved.

“All these creatures — whether hawks or squirrels — they know the lay of the land intimately,” Neil said. “Those squirrels know where every knothole is. They have a strategy to get into that cavity or nest to escape. They take the shortest route to get there. If they don’t make it, then of course, the reward for the hawk is a meal.”

There was a time when we humans were as intimately familiar with our environment.

“Most people — a lot — are losing a connection with nature, unfortunately,” Neil said. “Everybody’s wrapped up in and dependent on electronics and technology. That’s where a sequence like this is so pure. It reveals what’s happening every day that we just don’t see.”

In other words: That cute little squirrel digging in your garden? He’s the hero in his own action movie.

All week: Squirrels, squirrels and more squirrels!

Twitter: @johnkelly

For previous columns, visit washingtonpost.com/johnkelly.