This episode begins a 2-part story arc: “Affliction” and “Divergence.”
A fanatical group of xenophobes attempt to rid Earth of all non-humans and end all extraterrestrial relations.
4-06: The Augments
After turning against him, Dr. Soong assists Enterprise track down the Augments.
T’Pau and T'Pol's mother, both Syrrannites, assist Archer and T’Pol search for the Kir'Shara and uncover the truth behind the terrorist attack.
4-01: Storm Front, Part I
Trapped in Earth during World War II, Enterprise investigates dramatic changes in the timeline as a result of the Temporal Cold War.