She has been lead editor of Sports Illustrated Women and O, The Oprah Magazine and she has written several non-fiction books including The Devil's Teeth concerning sharks in the Greater Farallones National Marine Sanctuary in California.

Despite her re-vamp and being nominated for a National Magazine award the (now named) Sports Illustrated Women was discontinued at the end of 2002 by Time Inc.[2] Casey has written several non-fiction books.

She observed the dozens of sharks that are part of a research project by ornithologist Peter Pyle and Scot Anderson.

She also includes the sport of tow-in surfing using examples of surfers like Laird Hamilton who get their surfboards towed by boats to high speeds so that they can ride larger waves.

Captivated by mysteries held by the 98% of our biosphere which is in the dark, Casey spent years researching the book, including two deep dives in Hawaii and the Caribbean.