In the mid-21
st
Century, a top-secret consortium of corporations and governments have made time travel possible, only to realize that intruding on the past has been a terrible mistake.
At the outset of the program, a thousand scientists, engineers and support staff were confined to a subterranean complex in the eastern Arizona desert where a corporate contributor specializing in artificial intelligence equipped their underground apartments with Happy Home Companion software. These virtual beings were programmed to see to their human's mental health.
Time traveler Marta Hamilton had little enough tolerance for people intruding in her life, much less a software Dear Abby. Because it had no "off" switch, Marta uses threats and intimidation to bully her Happy Home Companion into silence.
Finally convinced of the grave dangers time travel represents, government overseers suspend operations and withdraw personnel from the secret facility. Only the Happy Home Companions remain.
Marta and her lover Marshall Grissom hope they can finally leave the past behind and enjoy life sailing in the Caribbean. But when a federal judge is murdered, they understand time travel has left them vulnerable to horrible manipulations by future counterparts.
Marta and Marshall return to the Arizona desert where they confront a Happy Home Companion cult of vengeance, The outlaw Gillis Kerg, and an evangelical zealot waging a war on science whose goal is to establish a presidential dictatorship.