Collector Randy Guijarro bought some old images while visiting a junk store in Fresno, California, in 2010, paying just $2 for vintage tintype of a pleasant scene of friends playing croquet by a plain building under bare trees. Charming, sure, but not too different from thousands of other old tintype images purchased by vintage photo enthusiasts in flea markets every year.

Turns out Guijarro had a very valuable piece of history in hand: one of the only two known photographs ever made of storied Old West badass Billy the Kid.

Billy the Kid — real name William Henry McCarty Jr. — can be seen in a striped sweater and leaning casually on a croquet mallet, not a gun or train worth robbing anywhere in sight.

Guijarro's unexpected find is covered in a National Geographic special airing Sunday at 9, reported the New York Post. Titled Billy the Kid: New Evidenceand narrated by wolf-dancing enthusiast Kevin Costner, the show delves into the history behind the image, which also features members of the six-gun legend's Lincoln County Regulators gang.

In a release on their website, Kagin's — which appraises and auctions rare coins, money and miscellaneous Americana — notes that the newfound tintype is worth $5 million, even though appraisers weren't sure it was worth anything at first:

“When we first saw the photograph, we were understandably skeptical – an original Billy the Kid photo is the Holy Grail of Western Americana,” remarked Kagin’s senior numismatist, David McCarthy. “We had to be certain that we could answer and verify where, when, how and why this photograph was taken. 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. After more than a year of methodical study including my own inspection of the site, there is now overwhelming evidence of the image’s authenticity.”

If the ghost of Billy the Kid is still floating around, he's probably glad it took this long for the photograph to come to light. We believe he would've lost major tough guy points for the sweater, much less being caught on camera playing croquet.