Dr. Ellen Prager is a marine scientist and author, formerly the chief scientist at the world's only undersea research station in the Florida Keys. With her ability to make science fun and understandable for people of all ages, she has built a national reputation as a spokesperson on earth and ocean science issues. She has appeared on The TODAY Show, Good Morning America, CNN, CBS, NPR, The Discovery Channel, and more. Dr. Prager has participated in research expeditions to locations such as the Galapagos Islands, Papua New Guinea, Fiji, and throughout the Caribbean. She now acts as the science advisor to the Celebrity Cruise ship Xpedition in the Galapagos. She lives in St. Petersburg, Florida, where she spends her days writing, consulting, and spending as much time on and in the ocean as possible.

Antonio Javier Caparo is an illustrator, comic artist, and graphic designer. His works have been published in children's books, middle grade books, and magazines in North America, South America, and Europe. He lives in Montreal, Quebec.

Being a teenager is never easy. Especially when you can talk to sharks! Tristan Hunt has enough to worry about with girl troubles, his parents, and trying to keep his extraordinary abilities a secret. But when Tristan and his friends are called upon to investigate the disappearance of stingrays and other ocean life in the waters off Grand Cayman, the stakes are higher than they've ever been before. Can Tristan solve the mystery of the missing stingrays and save them from a horrible fate? Or will he and his friends become the stingray-napper's next victims?

Join Tristan Hunt and the Sea Guardian on their most dangerous adventure yet.