You know from Harry's face that William doesn't stand a chance as the royal battle of the light sabers gets under way
(photo Kensington Royal Instagram)
Maybe it's Harry's more exuberant personality or his more relaxed air in public, maybe it's getting his own back for all the times that William played the big brother card as they were growing up but as they squared up with the sabers there was no doubt about who was winning this one. Harry meant business and he was taking no prisoners.
He all but snarled as he took on his brother in this mock fight - maybe William has seen it all so often he just decided to let him win. But whatever the reason, this part of the Star Wars tour was definitely all about Harry.
The royal brothers had arrived at Pinewood Studios for a tour of the production and sets of Star Wars - Kensington Palace said they wanted to help celebrate the ''fantastic British creative talent'' behind these huge, global films. The next Star Wars film - Rogue One: A Star Wars Story - was filmed in and around Pinewood.
It was also a good chance for the royal brothers to entertain themselves and everyone else by trying out things like light sabers. having a go with props and costumes and cuddling Chewbacca.
Harry seemed to enjoy more than William but then big brother showed a huge amount of interest in the tech behind the special effects. It was a brotherly endeavour all round.
There was plenty to take in and they met some of the stars of Star Wars as well as the many involved in putting it and keeping it on the cutting edge of film technology.
But when it came to the light sabers, there was only one winner. William's face said it all - in this realm, Harry is king.