After President Clara falls victim to a mysterious illness. Liz determines that the cause is a cold virus that she herself brought to Medusa from Earth. Octavia travels to Earth to bring back Professor Evans in an attempt to save the President's life.

At Octavia's request, Liz and Rudi investigate the abandoned records section. While Rudi searches for a way off Medusa: what Liz finds is far more sinister and distressing, an ancient experiment to create artificial life.