American intelligence officials uncover that Soviet spies have begun probing a remote region of the Alaskan Territory in search of answers to the worldwide reports of flying saucers. This high-stakes assignment lands on the desk of the wealthy American playboy Mike Trent, a man raised in those rugged frontiers, who is recruited by intelligence officer Hank Thorn to assist a Secret Service agent in the field and uncover what the Soviets may have found.
To Mike’s surprise, the assigned agent is an attractive woman named Vee Langley, and the two officers-in-disguise gradually develop a mutual attraction. Their cover story is that [Mike Trent] is suffering from a nervous breakdown and that [Vee Langley] is his private nurse. At Mike’s family wilderness lodge, they are greeted by a foreign-accented caretaker named Hans, who is new to the job and adds an uneasy note to the mission. Mike remains skeptical about the flying-saucer rumors until a sighting—an actual saucer gliding over the lodge—shakes his beliefs and raises the stakes of their dangerous assignment. Complications proliferate as it becomes clear that Hans is a Soviet agent intent on acquiring the saucer for his side.
The saucer itself is an invention of American scientist Dr. Lewton, but Lewton’s assistant, Turner, is a communist sympathizer who appears to be maneuvering behind the scenes to sell the device to the Soviets for a substantial payoff. The plot thickens as Mike’s journey to Juneau brings him into contact with old friends, including Matt Mitchell. Matt’s presence is more complicated than it first seems, especially when he becomes entangled with a bar girl named Nanette. Matt attempts to strike a bargain with the Soviet ring leader, Col. Marikoff, but is knocked unconscious in the ensuing struggle. He manages to escape and seeks out Mike, but the two are soon targeted by Soviet agents who kill Matt in a brutal confrontation. Before he dies, Matt reveals the saucer’s location to be at Twin Lakes.
Armed with this new clue, [Mike Trent] rents an aircraft and flies to the remote cabin where the saucer is hidden, then returns to his lodge with a renewed sense of urgency. He searches for [Vee Langley], who has been trying to spirit [Dr. Lewton] away, and the trio are finally captured by a turncoat, [Taylor], and a cadre of Soviet agents. The captives are herded through a secret tunnel that runs under the glacier, a perilous route that is finally cut short by a catastrophic avalanche. Mike, [Vee Langley], and [Dr. Lewton] manage to escape the tunnel just as [Turner] lifts off in the saucer.
In a sharp turn of fate, the craft suddenly explodes in mid-air because Lewton had planted a time bomb on board to ensure the mission’s failure could be a final, dramatic safeguard if things went awry. The immediate danger passes, and the surviving trio—Mike and [Vee Langley], in particular—are left to contemplate what they have accomplished, sharing a quiet, decisive moment of relief and a kiss that marks the end of a perilous chapter as their uneasy alliance gives way to a cautious hope for the future.
