An eccentric millionaire. A mysterious poem of clues. US$2 million of hidden gold. A trail of bodies who perished seeking their fortune.

The plot has all the elements of a time-worn adventure story, but the search for Forrest Fenn's buried treasure is all too real – even if the actual treasure may not be – as the families of four separate victims can now attest.

Jeff Murphy, a 53-year-old from Illinois, went missing last June after going hiking in Yellowstone National Park near the Montana-Wyoming border.

After an expansive search operation involving eight hiking teams plus dogs, horses, and a helicopter, Murphy's body was eventually found at the bottom of a rocky slope by the base of Turkey Pen Peak, which reaches about 2,130 metres (7,000 ft) above Yellowstone River.

Murphy had clearly died while trekking through the region's treacherous terrain, but while investigators of the accident discounted suicide as a contributor to his death, they didn't offer an official explanation of the accident.

The true cause of his misadventure was only revealed last week, when a local Montana news station filed a Freedom of Information Act Request into Murphy's demise, which discovered his mysterious end was part of a larger, stranger story.

Murphy, the report makes clear, died searching for the Fenn treasure, a hidden stash of riches buried by millionaire art dealer Forrest Fenn in 2010.

Fenn buried the treasure – an estimated US$2 million worth of gold coins and nuggets, ancient Chinese carved jade figures and precious gemstones – in a bronze chest, which he says is hidden somewhere in the Rocky Mountains in between Santa Fe and the Canadian border.

The treasure, which Fenn has disclosed is stashed at an elevation of 1,500 metres (about 5,000 ft) above sea level, is said to be secured in an accessible location that an 80-year-old man could reach (ie. Fenn himself hid it).

Nonetheless, the Rocky Mountain terrain can be so rugged that Murphy is in fact the fourth known person to die seeking the loot, with at least three other treasure-hunters – Randy Bilyeu, Paris Wallace, and Eric Ashby – having all met their demise searching for the fortune.

According to Fenn, who receives some 100 emails a day in relation to the treasure, more than 65,000 people have joined the search, attempting to decipher ambiguous clues hidden in a poem in his self-published 2010 memoir, The Thrill of the Chase.

The poem has 24 lines that are said to contain nine clues as to the location of the treasure chest – but while Fenn has acknowledged that many people have gotten some of the clues right, he says nobody has gotten them right in the correct order; although he admits many people have come close to the stash's secret hiding place.

Of course, many people think it's all a grand hoax designed to drum up publicity or sell the memoir, but even if it isn't, the string of fatalities linked to this deadly treasure chase have led authorities to pressure Fenn to "call off the hunt" - and so far, the millionaire has resisted such efforts.

His ultimate goal in starting the search was to "get the kids off the couch and away from the game machine," Fenn once said, and as long as that's happening, it looks like the dangerous game will continue – for better, and sadly, worse.

"Somebody could find it tomorrow and it may not be found for a thousand years. I'm looking at the big picture," Fenn told ABC News in 2015.

"A lot of people who are searching for the treasure don't see it the same way I do. I would love if someone found it tomorrow but if nobody found it for a hundred years, that's okay with me too."