Prince Harry could well have lobbed a “time bomb” that brings down the entire monarchy, one royal insider warned. 

In the explosive new documentary “King Charles: The Boy Who Walked Alone,” premiering on May 2 on Paramount+, several insiders — including ex-girlfriends and private staff — spill new secrets about King Charles and the rest of the royal family, ahead of the coronation on May 6.

Grant Harrold, the royal butler from 2004-2011, appears in the documentary to share his perspective on Harry’s recent behavior.

The prince has recently spoken out against the monarchy in his Netflix documentary “Harry & Meghan,” and in his controversial book, “Spare.” 

“At this point in time, there’s been polls done and the monarchy’s popularity has dropped,” Harrold said. 

“Charles, his popularity has dropped, Will and Kate’s popularity has dropped, Harry’s popularity has dropped.  What does that say for the future of it?  I don’t think Harry realizes that maybe he started a time bomb which could actually be the catalyst to actually destroying the monarchy,” Harrold cautioned.

Based off of his own personal experience and observations from his time with the family, Harrold also voiced skepticism about Harry’s allegation of getting into a physical brawl with William, which Harry detailed in “Spare.” 

“In all the years I was there, I didn’t witness fallouts [between William and Harry], I didn’t witness shouting. They were a happy family,” said Harrold. 

“So that bit [as described in “Spare”] doesn’t add up. I don’t know what’s made [Harry] change so much. I look at him, and I just — something has happened. Something has changed him and made him very different.”

The implication is that Meghan Markle has changed Prince Harry, although Harrold did not say that outright.

Royal insider Petronella Wyatt, a journalist and friend to Camilla Parker Bowles, spoke more bluntly in the documentary: “[Harry] was very close to his brother and he loved Kate. He’s changed a great deal. And it’s been since he married Meghan. So, draw the conclusion that you want.”

According to Harrold, Harry’s blabbermouth behavior is the main cause of the rift with his father.

“The one thing about Charles is that he’s very protective of the monarchy and he wants to ensure that it continues, like his mother did,” he said. 

“So if he feels that his son is going to damage or effect it, he has to make the decision, ‘Do I support my son, or do I support the monarchy? He will support the monarchy.”