Two young scientists are sent on a mission by the mysterious Dr. Eks. They are to exchange metal samples on Vanaris, a planet in another solar system. The Vanarians are mobilized into a police state and technology is at a standstill. Donkeys are the only means of transportation and the food — especially black mushrooms — is deadly for humans. The young men are prepared for danger, but not for certain surprises. When Jason discovers he is twelve years old with bumps on his forehead and Frank finds himself braying, there are ridiculous consequences — including an amorous donkey. With the help of a courageous girl, Jason and Frank confront the commander, Gru, and his spies. Scott Corbett combines suspense with a sense of humor in his first science-fiction novel.