Tom has his hands full as the resistance continues to battle the alien invaders. Tom's decision to have the rebel skitters fight alongside humans creates tension and raises suspicions that someone may be feeding secrets to the enemy.

With hostilities escalating between the resistance and the alien invaders, Tom calls on a nuclear specialist to come up with a plan that will strip the aliens of their power. As suspicion continues to mount about a mole, Tom and his leaders make a drastic decision.

The two-year anniversary of the alien invasion is fast approaching as the people of Charleston prepare for another potentially devastating offensive. A sniper attack by an unlikely gunman creates questions and doubts within the new government.

While Hal wrestles with an invasive evil, Ben struggles with his identity and the notion of being human again. Anne, meanwhile, uncovers startling new information that puts everyone in jeopardy.

When a mission goes terribly awry, Tom and Pope must rely on each other to survive. Weaver and company search desperately for two members of the 2nd Mass who have gone missing, and Marina takes matters into her own hands in Charleston, disregarding Tom's authority.

When a mission goes terribly awry, Tom and Pope must rely on each other to survive. Weaver and company search desperately for two members of the 2nd Mass who have gone missing, and Marina takes matters into her own hands in Charleston, disregarding Tom's authority.

The Masons run into trouble when a family of outlaws intercepts their search-and-rescue mission. Looming doubts over the construction of a massive alien weapon ignite a conflict of interests, and an investigation to apprehend a killer on the loose hits a road block.

Things seem much too calm for Tom, making him suspicious of his surroundings. On his way back to Charleston, he makes a number of discoveries, some surprising and others utterly horrifying. Meanwhile, Weaver and Pope butt heads over how to handle the suspected mole.

Tom uncovers confidential intelligence about the heart of the alien operation. As Charleston prepares to mount an offensive against the Espheni, an explosion brings the operation to a halt. The mole's identity is finally uncovered but not before the loss of more blood.

When the 2nd Mass destroys a crucial Espheni base, a relentless enemy is taken down and the Mason family is reunited with those who had been lost; but the arrival of more interstellar players puts the fate of the Earth's remaining survivors in doubt.