Plot: Andrew Graham-Dixon visits the new Lucian Freud exhibition at the National Portrait Gallery. Mark Kermode talks movies with author Geoff Dyer whose new book is based on the Russian cult classic 'Stalker', Charlie Luxton explores the churches of architect Nicholas Hawksmoor, Alastair Sooke looks back at the extraordinary life of Japanese artist Yayoi Kusama and journalist Aleks Krotoski investigates the transformation of the world wide web when the next billion people go online