Mo Yan, one of the country's most acclaimed authors, once wrote a novel for the big screen. It was turned down flat by the well-known film director, Zhang Yimou. ... Writer Su Tong, whose novels have frequently been adapted into movies and television series, says he has always remained cautious about book-to-screen adaptations, which he treats as "remote relatives". ... "Literature is like a drug like crack, except it has healthy side effects," the British writer [David Mitchell] says. "It alters the state of your mind, stimulates imagination and helps you understand other culture and other people."