Don Winslow of the Navy #67

In "Terror on the Tundras," Don Winslow and his companion discover planes flying through a northern mountain pass and follow them to an ice-free lake hidden among frozen terrain. They are captured by the enemy and taken to a fortress called the Scorpion, where a sadistic device called the Cage—designed to break men through psychological torture—awaits them. After two days of struggle across the frozen wasteland, Winslow escapes the Scorpion's prison and alerts Navy destroyers to sink the enemy vessel before the villains can complete their atomic bomb and use it against the fleet.