Forever Free (1999) (edit title/settings)

William Mandella, protagonist of The Forever War, lives with his wife Marygay on the icy world Middle Finger. Still dissatisfied with the state of society, they eventually decide to jump forward in time again, using the time dilation of interstellar travel. Their intention is to travel for 10 subjective years at relativistic speeds, during which 40,000 Earth years will pass on Middle Finger. They, along with other Forever War veterans and other disenchanted humans on Middle Finger, hope that whatever they will find upon their return will be more to their liking. This "experiment" requires the consent of the posthuman group mind now known as Man, and of the alien Tauran race. While it appears that they refuse permission, forcing the humans to take the ship by force, neither Man nor Tauran put up much of a fight indicating that those resident on Middle Finger did not share the views of the larger group mind.

Taking their daughter and leaving their son who has decided to join Man, they head away from their planet. However before they have gotten very far many unexplained occurrences happen and the ship starts to lose antimatter mysteriously. They abandon the ship and return home on fighters that have been converted into escape pods (although some people who believe it all to be a test by some deity remain aboard the drifting ship and are not mentioned in the text again). Instead of the intended 40,000 years, they have only been away 24 Earth years. Upon arrival, they find the planet still intact, but seemingly vacant with everyone having literally disappeared at the same time as the incident on their ship. They then return to Earth and in the course of the investigation they discover a shape-shifting being (similar to the "Chameleon" in his later novel Camouflage) posing as an android cowboy at a western-themed amusement park. This being has been on Earth and the other inhabited planets for millennia and is not certain of its own origin. It also has no idea what happened to the denizens of Earth.

The resolution involves an archetypal deus ex machina, a childish god who evidently created the universe on a whim but doesn't really understand it. This god recognizes Mandella as a scientist and explains that his action of leaving the galaxy on a 40,000 year round-trip is similar to a laboratory mouse escaping its cage. The galaxy would appear to be one large experiment controlled by these gods, an experiment damaged by Mandella's actions. Eventually "God" restores the inhabitants, who have been stored in stasis.

The story also focuses on William's and Marygay's relationship to their children, who do not agree with their parents' views, but still have to deal with their parents 'fleeing' into the future.

Forever Free is much shorter than the preceding book and also contained many printing errors in its first edition. The comic A New Beginning, the sequel to the comic version of The Forever War, was connected to Forever Free.

(from Wikipedia)