From the back:
"Mindkeep. The very name is mysterious. Why was it built? Who built it? What is its secret?
Your elite group of adventurers must find Mindkeep and learn its secret. Others have tried -- and failed. The surrounding area is filled with mutations that are strange even for Gamma World. Could that be a clue as to Mindkeep's purpose? Or is it mere coincedence?
The trek is long and difficult, across areas that are not well-known. Keep your wits about you, or you may lose everything!"