Adil is thrilled when one of his oldest friends, the legendary Ali Baba, drops in bringing wonderful news. Ali is about to get married to the beautiful Princess Sapphire - and Adil is asked to be Guest of Honour at the Royal Wedding in Balamkadaar. Determined not to miss out on "The Do of the Decade", Emma and Sophie wangle themselves an invite too. But there's a problem. Can the girls possibly persuade Dad to let them zoom off on a flying carpet to visit a magical, invisible city in the desert?