According to legend, the humanitarian Ransom founded the Independent Earth Colony on Axista 4 in the year 2437, but the truth is not as neat as the legend would suggest... 2537, 100 years since landfall, and all is not well. After years of failing crops a group of colonists, the Realists, have abandoned Ransom's back-to-basics ethos and have left to create a new high-tech settlement. The Doctor, Zoe and Jamie find themselves separated and drawn into the complex web of strained relationships between the two groups. As the Realists raid the remains of the colony ship for materials, the colonists must face the arrival of 80,000 refugees from Earth and confront the mysterious aliens who claim to be the planet's first colonists. Meanwhile, the Loyalists are intent on reviving Ransom's daughter from suspended animation in an attempt to unite the colony. Kirann Ransom, however, has a more personal goal - to find out the truth about her father and his actions at planetfall.