What happens when America's First Son falls in love with the Prince of Wales? When his mother became President, Alex Claremont-Diaz was promptly cast as the American equivalent of a young royal. Handsome, charismatic, genius - his image is pure millennial-marketing gold for the White House. There's only one problem: Alex has a beef with the actual prince, Henry, across the pond. And when the tabloids get hold of a photo involving an Alex-Henry altercation, U.S./British relations take a turn for the worse. Casey McQuiston's 'Red, White & Royal Blue' proves: true love isn't always diplomatic.