Captain Valentin Chang is en route to Florida in 2086 commanding the large submersible destroyer, Wynarte, as part of a coordinated, worldwide nuclear attack on major cities by the Sovereign Republic of Africa. As Wynarte waits for the appointed time to launch her missiles at Jacksonville, Orlando, and Atlanta, Chang discovers they are now in the year 2288.
Jake Myers is sent to San Francisco to fix a vacuum problem in the westward portion of the Transcontinental Underground Railway (TUR). He is helped by two maintenance workers and succeeds in correcting the problem in spite of a hostile attack. Thomas, one of the maintenance workers, confides that his grandfather related that he had traveled in time from WWII to 2234, so Jake meets with Thomas' family, assuring them that it was possible because he had also traveled in time from 2005 to 2283.
Juan Morales visits Jake and his family and relates that he is going to Savannah to reunite with Skye Davenport, and then to Jacksonville to find his former boss, Mason Bankowski, whom he hasn't been able to contact. Skye seems strangely distant and attracted to Mannard Heinrich, her employer, so broken-hearted Juan travels to Jacksonville. Finding a militaristic atmosphere, he contacts Jake, who joins him.
Together, Jake and Juan start their search, but are chased out of the city and captured by "outsiders." Jake finds a commonality with a leader of the outsider village and enlists their help. Meanwhile, Jake's family's concern over hearing nothing from him leads to his son, Nathan, traveling to Jacksonville, accompanied by Thomas, who volunteers to help.
Jake, Juan, and the outsiders search for answers within the city, while Nathan and Thomas independently do the same. They determine the city is populated by many soldiers, guards, and individuals under mind-control, and that many citizens have disappeared. WWII Nazis are included in the mix and someone called the Fuhrer seems to be in charge.
Thomas is captured and sent to an island prison housing the missing citizenry. Nathan discovers Jake is living with outsiders and sets off alone to find him, almost dying in the process. Jake and Nathan are reunited before Jake, Juan, some outsiders, and a few Nazi turncoats succeed in overtaking the island prison and rescuing the prisoners. Among the freed prisoners is Thomas' grandfather, Bill Reynolds, and two of his crewmembers from the WWII submarine, USS Crosshatch. Both Crosshatch and a German submarine, U-857, were transported from the same time, although U-857 arrived recently.
Juan, with help, rescues Skye from Mannard as they are being presented as the first Aryan couple, arranged by Karl Rudolein, a powerful Nazi trying to establish the Fourth Reich.
Chang intends to obliterate the area using his unfired nuclear missiles, but a skeleton ensemble of the 3 Crosshatch crew, Mason, Juan, Thomas, and the Nazi turncoats use U-857 to engage Wynarte. Both vessels are destroyed. Three survive unscathed, while Juan, Mason, and Bill are badly injured. As they seek medical help, Mannard tries to reclaim Skye and shoots Juan before falling to his death.
An epilogue set five years later reveals the fate of the characters.
