The story is set in 2158 A.D., after the invention of a medicine called Anti-Gerasone, which is made from mud and dandelions and is thus inexpensive and widely available. Anti-Gerasone halts the aging process and prevents people from dying of old age as long as they keep taking it; as a result, America now suffers from severe overpopulation and shortages of food and resources.
The flight into space that made Pilot-Capt. Dan Barstow famous. He was one of the very first astronauts to leave the earth -- and what he found surprised even him. "Another world." Small and too dark to see from the earth -- but large enough to capture his spacecraft. Large enough to get trapped on it.
Fear cut through the unconscious mind of Wilbur Hawkes. With almost physical violence, it tightened his throat and knifed at his heart. It darted into his numbed brain, screaming at him.He was a soft egg in a vast globe of elastic gelatine. Two creatures swam menacingly through the resisting globe toward him. The gelatine fought against them, but they came on. One was near, and made a mystic pass. He screamed at it, and the gelatine grew stronger, throwing them back and away.
The Gravity Gang was a group of geniuses--devoting its brilliance to creating a realistic Solar System for Disneyland. That was the story, anyway. No one would have believed all that stuff about cops and robbers from outer space.