Frank and Joe fly to Alaska to trace Scott Sanders, who's supposed to be working on a top-secret project for a mining firm. When company officials claim they've never heard of Scott, the Hardys grow suspicious. They find that some company managers have been selling jobs on the big oil pipeline. But before the brother detec- tives can dig deeper, they're kidnapped and forced to bail out over the Arctic wilderness. Stranded, Frank and Joe face their toughest test-fighting hunger, grizzly bears, and bullets to survive-while at trail's end a group called the Assassins waits to give them their final exam.