GettyImages-1094114874
Prince Charles and Camilla Parker-Bowles reportedly took secret trips to keep their affair from being exposed. The couple is pictured on a visit to the Supreme Court of the United Kingdom in London on Feb. 5, 2019.  Victoria Jones-WPA Pool/Getty Images

It’s never been a secret that Prince Charles and Camilla Parker-Bowles engaged in an affair before he ended his marriage to Princess Diana. Now, an explosive documentary claims that the two actually kept their relationship a secret by going on secret vacations together.

In the Amazon Prime documentary “The Story of Diana,” royal biographer Sarah Bradford revealed that the couple’s affair began in 1986—a full decade before his divorce from Diana was finalized and six years before they separated. At the time, the two decided to keep things on the down low by going on their secret rendezvous.

“They were certainly deeply fond of each other, Charles and Camilla,” Bradford said. “And they thought, ‘as long as we keep our heads down a bit, we can occasionally go on holiday together.’”

Of course, the trips didn’t work for long, as the pair was photographed together during a trip to Turkey in 1989, which her husband at the time, Andrew Parker-Bowles, also attended.

However, while they didn’t separate for several years, it’s believed Diana knew what was going on anyway, even by 1986.

“You could see it in the images. That was the other thing that was so transfixing about her,” ABC Correspondent Chris Connolly said in the documentary. “You could tell in the pictures how they were getting along.”

However, she wasn’t the only one who reportedly knew what was going on, as Charles’ grandmother, the Queen Mother, reportedly “didn’t mind” the affair as long as it didn’t result in controversy for the family.

“The Queen Mother is relatively broad-minded,” royal writer Piers Brendon said. “She didn’t mind Prince Charles having an affair with Camilla Parker Bowles, provided that this did not become a scandal.”