Yana Maddock, Sean Shongili, and their twins, Ronan and Murel, find their efforts to protect the planet of Petaybee threatened as the InterGal Corporation launches a bold assault that may destroy the peaceful planet's future.

Yana and Sean send their twin son and daughter, Ronan and Murel, to a space station to protect them from a scientist who wants to know how they can change into seals, unaware that the children want answers to the same question and may endanger themselves searching for the answer; and Sean dives into the depths in seal form to investigate bizarre changes to the planet.

The sentient planet of Petaybee has agreed to harbor a group of new refuges, workers indentured to the powerful InterGal Corporation. But the mission to collect the immigrants becomes a rescue operation.