World Without End

Returning from a Martian orbital exploration mission, the rocket RXM falls victim to an accidental acceleration. At a speed greater than 100 miles per second, the rocket ends its race in a chain of snow-covered mountains on a planet whose atmosphere is curiously identical to that of Earth. The four crewmen -- Commander John Borden, Herbert Ellis, Doctor Eldon Galbraithe, and Henry Jaffe -- have no choice but to explore this planet.

After having repelled giant spiders, our heroes must rapidly confront mutants straight out of the Stone Age. The crewmen theorize that the acceleration of the rocket provoked a curvature of time, and that they have returned to Earth in about the year 2200...