It's a mammoth tale of intrigue, antiquities, raids and recovery.

At the centre of it are the FBI, the RCMP and, oddly, the Canadian Museum of Nature.

Three woolly mammoth tusks returned to Canada after a raid a few years ago at the home of an American collector.

You can't help but hear the excitement in the voices of paleontologist Dr. Danielle Fraser and curator Kieran Shepherd, as they wheel in a cart carrying woolly mammoth tusks.

“It’s a good weight,” says Shepherd.

“That’s a heavy specimen,” adds Fraser.

It's not that these specimens are particularly amazing but their journey to get to the Canadian Museum of Nature sure is.

“It's not every day you get a call from the Embassy in Washington,” says Shepherd, the Curator of Paleobiology at the Canadian Museum of Nature, “saying “Hey, we have something that we believe belongs to Canada and we would like your help to repatriate back to Canada.  It was a pretty remarkable call, pretty exciting to me.”

The story of how the museum came to have the tusks is straight out a novel and involves a raid, a real-life Indiana Jones and the FBI.

News reports from 2014 show a home in Rush County, Indiana surrounded by agents with the FBI’s Art Crime team.  The home belonged to 91-year-old Donald Miller, a collector of artifacts and fossils that were housed in his rural home.  He had come under the scrutiny for the FBI that previous year.

“Mr. miller may have knowingly and unknowingly collected  artifacts, relics and objects of cultural patrimony,” Special Agent Robert Jones said at the time, “in violation of several treaties, federal and state statutes.”

Miller, who died almost a year after that raid, had amassed thousands of specimens including those woolly mammoth tusks and the FBI was determined to "repatriate" them.  They knew from Miller that the tusks had come from Canada during a trip in 1960 that he took between Calgary and the Yukon border.  Then, a few months ago, Kieran Shepherd got a call from the Canadian Embassy in Washington informing him that the FBI had something that they would like to return to Canada.

“I was pretty excited,” he says, “I've been with the museum for 30 years now and this is the first time I’ve been involved in the repatriation of fossils to Canada.”

Dr. Danielle Fraser estimates the tusks are between 10 and 20-thousand years old.

She believes they probably originated from the Yukon area, where these large plant-eating elephantids were known to roam during the Ice Age.  Two of the tusks are about 1.5 metres long, with a third, smaller tusk fragment.  And while Dr. Fraser says they are not particularly rare, their story makes them unique.

“To me, it is important that these fossils made their way back to Canada,” she says, “because they are part of our natural heritage but they also help fill in the gap about what we might not know about the natural history of mammoths in Canada.”

The tusks are housed in the museum's national fossil collections in Gatineau. They'll be on display during the Canadian Museum of Nature’s open house in October.