An extra terrestrial craft has landed in the mid-Atlantic ocean. Dr. Caffrey is a government contingency analyst whose job is to devise response plans for worst-case scenarios. In a single instant, her life changes when one of those plans-Threshold-is activated by the Deputy National Security Advisor. Armed only with her hypothetical strategy to address the appearance of aliens on earth, Caffrey now finds herself thrust in the midst of a global crisis. She hand-picks a team of eclectic specialists to prepare for first contact, and together, they decipher the intention of the craft, the fate of the ship's crew and begin preparations for the possibility of a crisis situation-an alien invasion.