Worlds Apart Pope seizes command of a renegade contingent within the 2nd Mass unit. Meanwhile, Tom suddenly returns to the group, but his loyalty comes into question; and Hal and Ben drift apart.
Shall We Gather At The River Tom is plagued by haunting memories of his time with the aliens and begins to speculate that they may have tampered with his mind. Elsewhere, Pope oversees an interview with Tom; Ben's hatred toward the skitters escalates; and scouts discover a bridge that could lead the group to safety.
Compass The unit moves into an airport hanger, but the relocation could cause health problems. Elsewhere, the renegade Berserkers scheme to cast out Tom; the unit copes with a loss; an enigmatic visitor provides hope.
Young Bloods Ben and Hal go on patrol and help a boy, only to have their bikes stolen. The subsequent search for the bikes leads to a major discovery. Meanwhile, Matt steps into a dangerous situation; and Weaver reconnects with a family member.
Love And Other Acts Of Courage A familiar person returns to the unit, but his motives are scrutinized. Elsewhere, a captured skitter is imprisoned at the camp, and Hal connects with Maggie as she casts light on her past.
Homecoming Hal happens upon bodies of de-harnessed kids and encounters a person from his past. Elsewhere, Tom and Anne inch closer together; and health issues plague Weaver.
Molon Labe Ben falls into a dangerous situation, thanks to a person he trusted. Meanwhile, Tom ensnares another captive; Weaver offers Matt a job; and the unit face a new enemy when they're trapped in the basement of a building.
Death March The unit marches onward to Charleston, S.C., as some in the group continue to grieve recent losses. Meanwhile, information surfaces about Tector's past; and Matt connects with a recently discovered harnessed girl.
The Price Of Greatness The 2nd Mass encounters new people as Tom happens upon his former mentor, yet trust issues abound. Meanwhile, Maggie suspects that Pope will soon exit from the group; and Tector embraces his military past.
A More Perfect Union The skitters draw nearer to the newly consolidated resistance force. Elsewhere, the 2nd Mass encounter their most perilous threat as Tom discovers game-changing information.