Jon Hamm and his Top Gun co-star Miles Teller may be big names in Hollywood, but even they get a little tongue-tied when they meet members of the royal family.MORE: Prince William reveals George, Charlotte and Louis's reaction to their parents' glitzy Top Gun outingLast week, the actors were introduced to the Duke and Duchess of Cambridge at the premiere of Top Gun: Maverick in London - an encounter that neither stars will forget in a hurry.WATCH: Tom Cruise talks about bond with Prince WilliamAppearing on The Tonight Show with Jimmy Fallon, the 51-year-old Mad Men star revealed: "It was black-tie, so we're all in tuxedos. And Prince William had on his tuxedo shoes, embroidered F-18s."MORE: Jennifer Connelly opens up about 'special' moment with Prince William at Top Gun premiereREAD: Inside Kate Middleton's inner circle of close friendsHe added: "Very cool Top Gun tuxedo shoes… that means you made it.