Go into the mammoth project of completing Tom Swift Jr.'s newest type of spaceship. It is a race against time and the stakes are high. First, Tom's foreign enemies appear ready to launch a manned moon rocket of their own. Second, the young inventor's friends on another planet propose a rendezvous in outer space, in the desperate hope that Tom and his scientist associates can help them conquer the unknown disease that threatens life on their planet.

From the first test flight to the day the Challenger roars moonward, Tom meets with frustrations and sinister perils, more challenging than he has ever encountered. In a neck-and-neck race with the enemy's rocket ship, Tom's fabulous invention, the super-repelatron, plays a dramatic part in heading off a crash landing on the bleak planet. One of the greatest thrills of the young space pioneer's life comes when he guides the Challenger alongside his planet friends' spaceship.

In this fast-moving, gripping drama of Tom's double victory in outer space you will find all the exciting elements that have made the Tom Swift Jr. series the Number One choice of boys who thrill to mystery and adventure.