One is the multimillionaire author of "The Da Vinci Code," the thriller that has remained at the top of the world's bestseller lists for years. The other is an unknown writer of school books from a small village north of London.
Dan Brown, whose novel was released on Friday as a US$193 million film starring Tom Hanks and Audrey Tautou, would expect to be far and away the more successful author, with worldwide sales of US$73 million.
But Naomi Simmons, whose books do not appear on any sales charts, has outsold him by more than two to one.
Simmons, from Shenley in Hertfordshire, north of London, is the author of "New Standard English," a series of text books for primary school children that has sold 105 million copies in China.
But unlike Brown, who has earned US$425 million from royalties for his novels, Simmons took a fixed payment of US$272,000.
Simmons and her co-authors became a phenomenon in China after the Ministry of Education decreed in 2001 that English should be taught in schools. Her book published by Macmillan English and FLTRP, the publishing house of Beijing University has inspired a generation of Chinese schoolchildren to sing songs about how the British use knives and forks rather than chopsticks.
Simmons said that the success was down to the radical nature of the books, which are designed to make the children laugh. "It has hit a spot," she said.
"They act out funny stories, sing funny songs and play funny games. When I visited, I saw the children singing the songs in the playground after class, without supervision. In a culture that is based on rote-learning, (our technique) is revolutionary. We are not even using such methods of teaching here in Britain."
The stories which have been made into cartoons and broadcast on China Central Television are a mixture of Chinese fables and introductions to English culture. In one, children learn about the English habit of putting milk in tea. "The Chinese people find that amazing," Simmons said.
The children are equally baffled by the idea that anyone would eat using a knife and fork. "Most children will never have heard of a knife and fork. The idea is incredibly exotic. In the same way we think chopsticks are funny the first time we go to a Chinese restaurant, they think it is very funny that we pierce peas with a fork."
Chris Paterson, the chairman of Macmillan Education, said that the sales were unprecedented. "This is the first course in modern China to have been written by international experts targeted at Chinese schools," he said. "Everything else has been written within China and it is rather old-fashioned."
There are 135 million primary school children in China, of whom 100 million are learning English.
Simmons, who developed the books with fellow authors Carlos Barcenas, Printha Ellis who died in a car accident in 2004 and Judy West, took a fixed payment from the books rather than royalties, but future editions may reward authors in proportion to sales.