A brilliant scientist has nearly perfected his time machine. His vision is to go back and fix the mistakes of history, eliminating war, hunger, epidemics, and the other scourges of mankind.
Naturally, everybody wants to get their hands on the machine and use it to acquire fame, fortune, and power. This includes the current vice president who wants to go back and wipe out everyone who now stands in the way of his path to absolute power.
The machine has been tested by sending articles forward into the future. Now it is time to send an intrepid explorer on two brief trips into the past to prove the machine and to work out the last few bugs.
The story takes place outside of Washington, Dc and in 1907 Appleton, Wisconsin.
But, there are two problems: First, any alterations to the course of history means that the lives and circumstances of the people of the world might be negated, and people who might otherwise never been born will take their place. Second, according to the second law of thermodynamics, it is impossible to simply send a person backward in time, but rather, he or she has to exchange places with someone equivalent who was living then.