What's shaped like a stingray and flies over Chesapeake Bay? This eerie riddle confronts Rick Brant and his friend Don Scott when, seeking shelter from a storm, they anchor the houseboat Spindrift in a lonely cove along the Maryland shore and spot the flying stingaree. The "thing," they learn, is not along, and residents of the Eastern Shore of Maryland believe the strange objects are flying saucers, but, weary of ridicule, have ceased reporting the sightings. Rick and Scotty, their scientific curiosity aroused, begin a comprehensive investigation, encouraged by their friend Steve Ames, a young government intelligence agent, whose summer cottage is near the cove. As the clues mount up, the trail leads to Calvert's Favor, a historic plantation house-and to the very bottom of Chesapeake Bay. How Rick and Scotty, at the risk of their lives, ground the eerie menace forever makes a tale of high-voltage suspense! (Volume 18 in the Rick Brant series.)