The game's story revolves around an extraterrestrial mineral, Siberite, that can catalyze cold fusion and serve as fuel for an alien artifact. Siberite and the artifact - named EON - are discovered by a U.S. expedition to Russia during World War I. EON is revealed to be a time machine capable of sending objects into the past, but by the time of the discovery, Siberite stocks are exhausted and research stops. Then in the new millennium vast deposits of the mineral are found in Siberia, and Americans are able to extract enough of it for small-scale time-travel.

The U.S. comes up with a plan to send a small force two million years back in time. There it will mine the Siberite and transport it over the Bering Land Bridge to Alaska, into what will one day be in American hands. The best troops are selected, briefed, and told that it is a one-way trip back through time.

This results in a new time line with the mineral located in Alaska and the U.S. being the only undisputed superpower thanks to the inexhaustible source of energy. Here the time machine wasn't found by the U.S. but the Russians instead. The USSR fumes under American supremacy. Frustration turns to outrage when Soviet scientists find traces of American settlement and Alaskite, the source of U.S. power, in remote Siberia. A Soviet expedition is sent through the EON, here called TAWAR, to repel the American thieves and preserve what is rightfully theirs.