Much jollyment was had, with pictures of the twosome cuddling Chewbacca and spending time with castmembers including Daisy Ridley and John Boyega and standing near cool looking spaceships.
But it seems it wasn't all fun for the Royals, as they may also have filmed a part for the upcoming movie. A rumour is suggesting that the pair got suited up in Stormtrooper costumes for a scene involving Boyega, Ridley and new castmember Benicio del Toro in a lift.
The news comes from an insider via The Daily Mail and apparently it all happened while everyone was told the two men were off having lunch. If it turns out to be true, it wouldn't be the first cameo for the series, with James Bond himself Daniel Craig popping up in The Force Awakens.
That's on top of secret-ish appearances by Simon Pegg, Ewan McGregor, Warwick Davis, Kevin Smith and Bill Hader lent his pipes to BB-8!
Star Wars Episode VIII is in cinemas in December, 2016.