During the audacious crime, which could have come straight out of a movie, back in 1971, the man jumped up on the Northwest Orient Airlines 727 flight, shortly after it took of from Portland, telling terrified passengers, he had a bomb.
Then after landing at Seattle Airport, the man who gave his name as Dan Cooper, exchanged the terrified passengers for a huge $200,000 ransom, before forcing the pilots to take off and head for Mexico.
But he never made it south of the border, as at some point during the flight, he parachuted out the plane, never to be seen again.
Now four decades later, G-men think a tip from a fellow law enforcement member has led them to a person who might have helpful information on the brazen hijacker.
Amy Sandalo, told the Seattle Times it was the "most promising lead we have right now," but cautioned that investigators were not on the verge of breaking the case.
She added that an item belonging to the man was sent to a lab in Quantico, VA. for forensic testing. However, she did not provide specifics about the item or the man's identity.
Investigators have checked more than 1,000 leads since the suspect bailed out on Nov. 24, 1971, over the Pacific Northwest, to no avail.