A radio message from a whaling company draws Storm to the Weddell Sea to solve the mystery of three missing catchers, with nothing to guide him but the drawing of a sea leopard and the fear of a phoney electrician. With the ever-ready support of Bash, Spanner, Jonah, and Kerfuffle - the crew of the Silver Fleet - he discovers the unsuspected fate of the lost vessels and their crew, but not before he has encountered the dreaded Sea Leopard. Even then, only half the danger is over, for the Silver Fleet's most relentless enemy - the ice trap - lies in wait on the homeward trip...