There are many things that puzzle Tom Swift. But among the most vexing in recent times is the discovery of an impossible planet, and one that has existed within the solar system for possibly as long as the Earth. Yet, it has gone completely overlooked and undetected. Now, as Tom supervises a mining operation in the asteroid belt remotely from Shopton, a mysterious something crosses a million miles in front of his ship, the Sutter. Like a ghost in the corner of a dark room, it is vaguely there and yet it is not. And so, he decides to find out just what it is. What Tom and his crew find is a planet that is not the ordinary spherical shape. It isn't even a rough piece of rock as with almost every asteroid other than Ceres. It most certainly is not Ceres. How it manages to remain together is one mystery to solve, but when he attempts to land on this invisible planet, all he finds is a type of chaos that is enough to make even the most sane man think he is crazy! Join Tom as he finds out the truths about the mystery planet that has been "out there" practically forever.