In the year 2046 the Global Government had managed to make contact with another race outside of Earth. But they weren't happy about being discovered and came to destroy Earth.
The Shell siblings did not have an easy upbringing after their families death when Ellie was only six and has a three day missing gap from her memory when she was nineteen. What happened to her during those three days? At least the siblings have each other on the colony ship after Earths distruction.
The High Commander put a great majority of his ward in cyro-sleep so his team can find a liveable planet to inhabit. When the Shells wake up 128 years later, what happens when the planet is not only liveable but already has intellegent life populating the planet? What are the secrets of the Shell family? Why are memories flooding back that the three don't remember ever having?