Nick Harkaway's Karla's Choice is a thrilling return to the world of spy fiction's greatest writer, John le Carré. Nick Harkaway, whose real name is Nick Cornwell, talks to author and journalist Alex Preston about the shadowy world of George Smiley created by his father David Cornwell, who wrote as John le Carré – and why he decided to re-introduce the redoubtable agent and his steely nemesis in this page-turning plot of deceit and danger.Nick Harkaway is the author of eight novels, including The Gone-Away World, Gnomon and Titanium Noir.

Alex Preston writes for the Observer and the Guardian. His books include In Love and War; As Kingfishers Catch Fire; and Winchelsea.