SEATTLE -- On Thanksgiving Eve 1971, a man named Dan Cooper boarded a plane headed to to Seattle-Tacoma International Airport and showed a flight attendant a bomb.
At the airport, Cooper released the passengers in exchange for $200,000 and four parachutes and asked to be flown to Mexico. He jumped from the plane somewhere near the Oregon state line. His body has never been found.
And so begins the story of D.B. Cooper. It's been told many times over, but the famous Northwest hijacking mystery has never been solved.
Without an explanation, many have provided their own endings to the story. Some even claimed to be related to the legendary thief. Others paid thousands of dollars for tattered $20 bills of the recovered ransom money.
John Detlor and Bob Fuhriman have spent years thinking about what might have happened to Cooper after he jumped. The two were on duty when the FBI received its first D.B. Cooper call.
"I looked at an agent near me and said, 'what's a hijacking?'" said Fuhriman.
Before he knew it, the agents were already on the move.
"The big race was probably getting the parachutes," said Detlor.
Detlor set about getting the chutes while another agent worked on getting the money.
When Cooper freed the passengers and took off for Mexico, it never occurred to the agents he was only along for a part of the ride.
"Nobody really expected him to jump," said Detlor.
But Cooper did jump, from 10,000 feet up in the air, never to be seen again.
Back in Seattle, meanwhile, Fuhriman sorted the freed passengers for FBI interviews. That's when he heard a reporter ask for the hijacker's name.
"Somebody said something like 'D.B Cooper.' I heard 'D.B. Cooper' there," he said.
The name stuck and the mystery grew. Cooper, meanwhile, grew into a legend.
"In America, there's kind of a folk hero type of thing that can get started sometimes," Fuhriman said. "When you really look at it, they're anything but a hero."
Every so often, something new surfaces and even those who had stopped wondering get pulled back into the mystery all over again.
Just a few months ago, an old parachute was found near Amboy. The FBI initially thought it may have been Cooper's, but that later proved to be false.
Officially, the FBI believes Cooper died in the jump. But other hijackers who later copied Cooper's crime managed to survive.
Fuhriman and Detlor say the FBI has questioned more than a thousand suspects over the decades. But the case remains open, and the FBI believes a new lead could jump start the case.
The retired agents decided to share their stories as the FBI celebrates its 100-year anniversary.
Puyallup couple: Cooper had sex change operation
A local couple has written a book which claims D.B. Cooper managed to escape the law by becoming a woman.
In Legend of D.B. Cooper: Death by Natural Causes, authors Ron and Pat Forman claim the famed hijacker was their friend who had a sex change operation. They say Barbara Dayton admitted she was Cooper before she died in 2002.
The FBI reviewed the claims and said Dayton was too short and had the wrong-colored eyes to have been Cooper. But Ron says he has his own suspicions about the FBI's claims.
"If it came true that she got away with this and lived a normal life and died of natural causes, it might be (that) they don't want to see the publicity," he said.