 Those pages would comprise the first four chapters, and the full manuscript received a $7,500 total advance.Congdon and the Doubleday crew were confident, seeing Benchley as "something of an expert in sharks", given the author self-described "knowing as much as any amateur about sharks" as he had read some research books and seen the 1971 documentary "Blue Water White Death".After Doubleday commissioned the book, Benchley then started researching all possible material regarding sharks.