Lucius Tode, James Dent and Miles Parrish had been conducting investigations into the structure of the atom. Now Tode has modified an atom-smasher into a time machine to travel to the paleolithic age and Atlantis. This can't be good! It's up to Dent to discover Tode's intentions and stop him before it's too late. It was sublime and terrible, and on the result of that conflict depended-what? Four destinies rocket through the strange Time-Space of the Fourth Dimension in Tode's marvelous Atom-Smasher.