​The hunt for Forrest Fenn's treasure

He drove out across the Rockies and left the chest.

Clues to a hidden treasure

"There's 265 gold coins, eagles and American double eagles," he said of the chest's contents. "And there's hundreds and hundreds of gold nuggets. You're gonna be amazed at what you find.

"And when I walked back to my car, I talked to myself out loud -- there was nobody around anyplace - and I said, 'Forrest Fenn, did you really do that?' And I started laughing."

Fenn then wrote a poem with nine clues placing the treasure somewhere in the Rockies in one of four states -- Montana, Wyoming, Colorado, or New Mexico.

Petersen asked Fenn, "Do you wanna add anything to the hints?"

"The treasure is not hidden in a mine. A lotta these old mines are dangerous. I mean, they have snakes in 'em, they have black widow spiders!"

"Well, that's a good hint and a good piece of advice."

"Did I give you a hint? Really? You're not being fair to me, Barry!"

"Well, I don't think that narrows it down a lot, I gotta tell you."

Lust and loot, it turned out, launched a lot of lookers. Fenn says he stopping keeping track of emails at 65,000. Add to that countless more online with their own plans to find the treasure:

But, is it REALLY out there?

Death threats over a hidden treasure

"The only way that I could prove to you that the treasure is hidden is to take you there," Fenn said. And he won't. "There's an old saying: 'Two people can keep a secret if one of them is dead.' So if I take you out there, I wouldn't wanna be your insurance agent!" he laughed.

To avoid that deadly fate, we opted to just ask someone who knows a lot about secrets: his friend, Valerie Plame. A former CIA agent, her cover was compromised in 2003 by a White House official. Scandal ensued, and Plame and her husband eventually moved to Santa Fe, where she met Fenn.

She says Fenn hasn't told anybody his secret. "Apparently not even his wife," she laughed. "That is something!"

"Do you believe him?" asked Petersen. "Do you think that treasure's out there?"