How Ben Affleck and Jennifer Garner's Son Ended Up Playing With Prince George and Princess Charlotte!

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Hollywood royalty meets actual royalty! Ben Affleck and Jennifer Garner’s son Samuel got the ultimate celebrity treatment while his famous dad was in London filming Justice League.

The 44-year-old A-list actor visited The Graham Norton Show in an episode that airs on Friday, where he opened up about a very unique experience he and his family happened upon by accident across the pond.

WATCH: EXCLUSIVE: Jennifer Garner on Teaching Her Kids to Be 'Citizens of the World': It's the 'Best Thing You Can Do'

“Despite going to Windsor Castle, Tower of London and Buckingham Palace,” Affleck noted in quotes released as a promo for the show, “we didn’t see one royal. Then when it was raining I took my youngest [Samuel] to one of those kid’s indoor play parks. It was pretty empty and then I noticed this weird vibe from the other grownups.”

Affleck quickly realized he was not at just any playground.

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“I thought, ‘For a kids’ place this is tight security!’ I was the very last person to realize that Prince George and Princess Charlotte were in there playing with my kid,” the father of three revealed. “I can now tell him that he got a cold from the King of England!”

Affleck didn’t note if Prince George or Princess Charlotte’s parents, Kate Middleton and Prince William, were also at the park, but he did say that he took his kiddos to see some of the historic London landmarks.

MORE: Ben Affleck Implores New Hampshire Citizens to Vote by Doing His Best New England Accent

“We did all the sights and I wanted them to be cultured. Now if it was in America – and I hate to admit this – you’d get a VIP pass, you’d get backstage and they would accommodate you,” Affleck told the British crowd. “So I got a tour guide thinking this guy will accommodate me but that wasn’t the case! He took us to the middle of the street but we were so far away not only couldn’t we see the guard, we couldn’t see the fence! We were surrounded by 50,000 tourists looking for selfie opportunities and we never saw the guards change. It was a disaster!”

The Graham Norton Showteased Affleck’s appearance via Twitter Wednesday. “This Friday! We have @BenAffleck, Sir David Attenborough, #MattSmith, #ClaireFoy and music from @OfficialSting 10.35pm on @BBCOne #TheGNShow.”

Garner, Affleck’s estranged wife, recently opened up to ET about teaching their kids to become “citizens of the world.” Watch the exclusive interview below!

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