Liane Moriarty has achieved something no other Australian author has: her novel Big Little Lies is the first to debut at number one on the New York Times bestseller list. Just one of her six international bestsellers, Big Little Lies has been made into an acclaimed HBO TV series starring Nicole Kidman and Reese Witherspoon. Helen McCabe talks to Liane about the recent release of her latest novel Truly Madly Guilty and the secrets of achieving world acclaim.