'It ain't no unicorn': Meet the researchers who've interviewed 130 Bigfoot hunters

It was the image that launched a cultural icon. In 1967, in the northern Californian woods, a seven foot tall, ape-like creature covered in black fur and walking upright was captured on camera, at one point turning around to look straight down the lens. The image is endlessly copied in popular culture—it's even become an emoji. But what was it? A hoax? A bear? Or a real-life example of a mysterious species called the Bigfoot?