Korean War fighter pilot Ace Morgan is flying through a storm, on the way to bring himself and three others to a news radio station. Each of the three, like Ace, is famous in their field: Olympic wrestling champion Rocky Davis, skin diver Prof Haley, and circus daredevil Red Ryan. When the plane is struck by lightning, it crashes to the ground. The plane is destroyed; however, all four somehow manage to survive the mangled wreck. When Red notices that his damages watch still works, Ace mentions that they are “living on borrowed time.” The four agree not to squander their borrowed time, and decide to dedicate their time to become “ Challengers of the Unknown.”
The Challengers receive a letter from a man named Morelian. He asks for the Challengers to come to the Canadian wilderness in exchange for a million dollars. The Challengers take the dare, and meet Morelian at his castle in the wilderness. The team find out that Moredain is a sorcerer, and teleports them to his laboratory. Moredain shows them an ancient box with four chambers and, if they dare and if they survive, they will receive a million dollars for opening it.
The Challengers decide to take as many precautions as possible, and treat it as if it is an atom bomb. They bring the box to the uninhabited Aku Island. After the drawing of straws, Rocky gets to take a stab at the box. He opens a chamber, and finds a giant egg. The next day, the egg hatches into a stone giant. The giant grabs Red, and leaves the island. While Ace and Prof chase down Red and the giant, curious Rocky opens the second chamber.
Red is rescued by the navy, and rows back to Aku Island, where he finds Rocky frozen solid. Red and the navy discover the “Freezing Sun,” a telepathic sun that sucks the heat out of the two navy men. Red’s quick thinking traps the sun in a vacuum chamber, while Prof’s quick thinking lets him realize he can “wish” away the giant. Prof and Ace return to Aku, and meet back up with Red and a thawed out Rocky.
Ace opens the third chamber, which exposes a canister that wraps him in silk. Inside the canister was a remote drone, that the Challengers learn to control via the canister. With three chambers open, the Challengers go to open the fourth, but find Moredain has already done so. Moredain knows one of the chambers holds the secret to immortality, and let the Challengers risk themselves. Moredain dons the ring in the fourth chamber, but ends up dying in a plane crash leaving the island. The Challengers discover that the secret to immortality was not the ring, but the box itself.
"Shorty" by Henry Boltinoff
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