Author: BLAKE ELLIS AND MELANIE HICKEN, CNN INVESTIGATES

'Easy prey': How a massive psychic fraud gained its power

CNN journalists Blake Ellis and Melanie Hicken have spent years investigating one of the largest consumer frauds in history -- a case that has stumped global investigators for decades. The scheme, which duped victims out of millions of dollars with letters claiming to be from a famous French psychic named Maria Duval, is the subject of the reporters' new true crime book, "A Deal with the Devil." The following excerpt has been edited for brevity.

How to get off a scammer's suckers list

Kip Koelsch saw the hundreds of pieces of mail arriving at his father's home every week. But it wasn't until the 84-year-old called him saying he'd won a Mercedes and a million dollars that he really began to worry.