The identity of skyjacker D.B. Cooper—a well-mannered passenger on Northwest Orient Airlines Flight 305 who parachuted out of the skyjacked plane heading to Seattle in November 1971 with $200,000 in cash—has long intrigued both law enforcement and amateur sleuths. One theory posited that Cooper may have even been a woman in disguise.

In July 2017, the FBI officially closed the case. This week, they might take another look at their archival material. An 84-year-old pet sitter from DeLand, Florida named Carl Laurin has made a public proclamation that a deceased friend of his, Walter R. Reca, once admitted he was the country’s most notorious airborne thief.

The announcement is tied to the publication of Laurin’s book, D.B. Cooper & Me: A Criminal, a Spy, and a Best Friend. And while some may discount the admission as an attempt to sell books, the book's publisher—Principia Media—claims it vetted Laurin’s claims via a third-party investigator.

According to Laurin, he and Reca met while both were skydivers in the 1950s and kept in touch over the years. Reca was a military paratrooper and received an Honorable Discharge from the Air Force in 1965. Laurin suspected his friend immediately following the skyjacking since he had previously broken the law, including an attempted robbery at a Bob’s Big Boy restaurant as well as several banks. But Reca didn’t admit guilt until shortly before his death in 2014, when he handed over audiotapes of his confession and made Laurin promise not to reveal them until after he had passed away.

Principia Media publisher/CEO Vern Jones says he expects skeptics to challenge the book’s claims, but says that the evidence provided by Laurin was “overwhelming.” The FBI has yet to comment on any of the specifics of Laurin’s story, but an agency spokesperson told The Washington Post that “plausible theories” have yet to convey “necessary proof of culpability.” Nonetheless, someone at the Bureau probably has a weekend of reading ahead of them.

[h/t MSN]