It's shaky, famous and was filmed in the north state 40 years ago today.
Some say the Patterson-Gimlin film proves the existence of the legendary Bigfoot.
Others say it's an elaborate hoax and had to be a guy in a hairy suit.
You might not recognize the names, but you've likely seen the footage. A massive, furry biped -- perhaps Bigfoot -- lumbers along the bank of Bluff Creek near where the Trinity and Klamath rivers collide, turning back to glance toward the nervously held 16-mm camera.
While the film runs only about a minute, its effect on the debate over Bigfoot's existence has been lasting.
"It's longer and clearer than anything else," said John Green, a former Canadian newspaper publisher who has been trying to track down Bigfoot since 1957.
Green is familiar with just about every piece of alleged Bigfoot film, photo and plaster that has surfaced in the past half-century. He has a collection of 4,000 reports, detailing when and where people say they saw the big animal.
The best evidence out there still is the film, he said.
The film was shot by Roger Patterson who was trying to get footage of fresh Bigfoot tracks for a documentary, Green said. Robert Gimlin was along for the adventure into the north state backcountry.
Recent tracks had been found near Bluff Creek, which drew Patterson and Gimlin for an expedition, said Jeffery Meldrum, associate professor of anatomy and anthropology at Idaho State University in Pocatello, Idaho. The duo didn't find Bigfoot right away.
"They'd been putting in their time in the saddle for a couple of weeks," he said.
Exploring the rugged terrain on horseback, the pair saw a massive, hairy figure on the afternoon of Oct. 20, 1967.
The film is shaky because Patterson is running with the camera in hand after hastily dismounting and digging his camera out of his saddlebag. As he gets close, the beast looks back over its shoulder and shoots a stare right at Patterson.
He later described the stare to Green.
"You know the look when an umpire says, 'One more word and you're out of the game'?" Green said.
Shown in movie houses around the U.S. and Canada shortly after it was shot and now a part of several Bigfoot documentaries, the film has been at the epicenter of the Bigfoot debate for decades -- believers say it's proof and doubters say it's a sham. Despite 40 years of scrutiny, the film, unlike many others said to be of Bigfoot, hasn't been proved to be a hoax.
Patterson died of Hodgkin's disease in 1972, so Gimlin has been alone in recounting of what happened that day. Tired of taking grief over whether the film was real or not, he often turns down interview requests, although he started speaking at Bigfoot conferences in recent years.
A woman who answered Gimlin's phone said he didn't do interviews, although she agreed Thursday to pass him a message. He didn't call back.
Patricia Patterson, Robert Patterson's widow, also declined an interview request. She owns the rights to the film, but declined to give permission for use on Redding.com.
Rights for still photos from the film are owned by Erik Dahinden, a Canadian whose late father also sought Bigfoot and obtained the rights in a court decision. He said he would allow use of the photo only for a price.
Gimlin has spoken to Meldrum about his experience. He told him that he got a closer look at the beast than Patterson because he wasn't looking through a viewfinder.
"He was impressed with what he saw," Meldrum said. "The musculature. The naturalness of its gait. He was confident what he saw was a real animal."
Scientists who have vetted the film note the movement in the animal's joints and length of its bone structure that Green says show it is too big to be a man.
"It is simply not built like a human," Green said.
The footage also appears to show an animal with breasts, leading researchers to say that it was probably a female Bigfoot.
Among the believers in the film is Brian Campbell of Redding, who says he has gone on expeditions into the deepest north state woods in search of the creature since he saw one near Lassen Peak as a teenager in the 1970s.
He said the animal in the film is the same as what he saw in the woods.
"That's a real Sasquatch," Campbell said. "That's a real Bigfoot, definitely."
Reporter Dylan Darling can be reached at 225-8266 or at email@example.com.