This week, Graydon Carter takes us inside a special edition of Air Mail that is all about London, and he shares the places he loves there. Then the acclaimed writer Will Self will share his version of “the Knowledge”—London cabbies’ ability to navigate their streets without a map—by sharing treasures he’s discovered over a lifetime of walking his native city. And speaking of knowledge, Stuart Heritage tells us about his afternoon with the gentleman who is often called “the best-connected man in Britain.” And finally, it’s been said that the U.S. and the U.K. are “two nations divided by a common language.” Well, Hannah Betts swings by to discuss the four-letter word beloved by Brits but hated by Americans that validates this divide more than any other. And let’s just say it’s a word that we can’t even bring ourselves to utter. All this and more make it a show you won’t want to miss.