In 1983, Grey published "The Prime Minister Was a Spy", in which he claimed that Harold Holt (prime minister of Australia from 1966 to 1967) was a spy for Communist China, and that he had not drowned, but in fact had been "collected" by a Chinese submarine and lived out the rest of his life in Beijing. The book was widely ridiculed, and Holt's biographer Tom Frame has described it as "a complete fabrication".