Randy Bilyeu set out early this month on an obsessive quest to find $2 million in gold buried by an eccentric millionaire.
He hasn't been seen since.
INSIDE EDITION spoke with his daughter, Carissa, who said her dad "is adventurous, he liked the thrill of it. He liked being outdoors. He told me that it kind of connected him spiritually."
Bilyeu had been fascinated for years with The Thrill of the Chase, a book written by millionaire Forrest Fenn, in which he claimed to have buried a chest full of gold somewhere in the Rocky Mountains.
Clues to the treasure were included in the book, and Fenn also gave hints on television, captivating the imaginations of thousands of seekers.
Bilyeu, 54, set out in a raft, with his dog and supplies, and drifted down the Rio Grande. The vessel, and Bilyeu's pet, Leo, were later discovered downstream. The dog was alive, but its owner was nowhere to be found.
Bilyeu was searching for the hidden fortune in areas not mentioned in Fenn's book. His route, which he said he designed after scouring the millionaire's writings, baffled his daughter.
"He had some kind of a plan that bewilders me, quite frankly," she told IE.
Then his car was found in a remote area outside Santa Fe, New Mexico. In it were boots, water, a Thermos, and dog food.
Fellow treasure hunters have joined in the search for Bilyeu, as has Fenn.
"We are hoping for answers real soon. We are hoping that he is still alive," his daughter said.