Director Oliver Stone discusses his latest TV documentary series. The Untold History of the United States; Shahidha Bari reviews the Tate Modern's major exhibition of work by Saloua Raouda Choucair; US Country and Western singer Kacey Musgraves discusses the inspirations for her music; Howard Brenton on his new play about the imprisonment of Ai Weiwei; David Baldacci on the art of writing crime thrillers; William McIlvanney discusses his new Laidlaw trilogy of novels.