Ten years after its mysterious disappearance, the seaQuest appears back on Earth.

A tough Navy officer, who had been obsessed with searching for the submarine, assumes command of the seaQuest due to the new hostile world climate.

When Henderson is captured by Macronesia and sentenced to death, Hudson leads an undercover team to free her from the secure facility.

Lucas must face up to Bridger over his potentially risky solution to combat an organism that threatens to reach epidemic proportions.

The crew members travel through a ""space-time sphere"" that rockets them back in time to October 1962.

This places them in the midst of the Cuban missile crisis where they have to try to prevent a nuclear holocaust.

The seaQuest is drawn into the dangerous neutral area where the UEO and Macronesian borders meet the territory of a silent and elusive Asian power.