In 2010, collector Randy Guijarro was browsing a junk shop in Fresno, California, when an old photo caught his eye.
The image depicts a group of Lincoln County Regulators playing croquet in the summer of 1878, the New York Post reports. Among those men is William Henry McCarty Jr.
Most people know him as the legendary outlaw Billy the Kid.
Guijarro paid $2 for the tintype photo, which could now fetch $5 million.
(Billy the Kid (left) playing croquet with his gang the Lincoln County Regulators)
(Full picture of Billy the Kid and the Lincoln County Regulators)
“When we first saw the photograph, we were understandably skeptical — an original Billy the Kid photo is the Holy Grail of Western Americana,” said numismatist David McCarthy, according to the New York Post.
A numismatist is someone who studies or collects currency, such as coins, tokens, paper money and other related items.
McCarthy is a numismatist for the Americana company Kagin's, which is negotiating the price of the photo.
“We had to be sure we could answer and verify where, when, how and why this photograph was taken," McCarthy added. "Simple resemblance is not enough in a case like this — a team of experts had to be assembled to address each and every detail in the photo to insure that nothing was out of place.”
Kagin's auction house has officially authenticated the photograph and has valued it at $5 million.
A new Nat Geo Channel special, "Billy the Kid: New Evidence," narrated by Kevin Costner, will delve into the photo's back story. The special will air at 9 p.m. on Oct. 18.
When he bought the now-famous photo, Guijarro had no idea that his $2 investment would make him rich. He was rummaging through two cardboard boxes full of pictures when he noticed the tin type, and a voice in his head told him to grab it, ABC reports.
"So I picked it back up and said, it's got a hole on top, kind of beat up," Guijarro told ABC. "Okay so I got those three photographs for two bucks."
It paid off.
"This is the first photograph ever discovered of Billy the Kid with The Regulators, period," said Jeff Aiello, the executive director of the Nat Geo special. "And that's significant in American history."
The only other iconic Billy the Kid picture sold in 2011 for $2.3 million.
"...it's the holy grail of not just western photography," Aiello said. "It's the holy grail of photography. It is the rarest photograph in the world and it was found in a Fresno junk shop."