The 1958 version: At the end of the Twentieth Century petty crook Ross Murdock is given the choice of facing a new medical procedure called Rehabilitation or volunteering to join a secret government project. Hoping for a chance to escape, Ross volunteers to join Operation Retrograde and is taken by Major John Kelgarries to a base built under the ice near the North Pole. Teamed with archaeologist Gordon Ashe, he is trained to mimic a trader of the Beaker culture of Bronze-Age Europe.
Sent back to southern Britain around 2000 B.C.E., Ross and Ashe (as Rossa and Assha) find that their outpost has been bombed, destroyed by the wrath of Lurgha, the local storm god, according to two of the natives. Discovering the direction whence the bomber came and other clues pointing to the general area occupied by the Soviet base, Ross, Ashe, and McNeil, the lone survivor of the bombing, go to that area.