Falling Skies opens in the chaotic aftermath of an alien attack that has left most of the world completely incapacitated. In the six months since the initial invasion, the few remaining survivors have banded together outside major cities to begin the difficult task of fighting back. Each day is a test of survival for these citizen soldiers against the occupying alien force, whose nature and purpose remains a mystery. The mystery deepens for the remaining survivors of the massive alien invasion as Falling Skies returns for its second season with mysterious new creatures.

Three months have passed since former college professor, father of three and unlikely leader of the civilian resistance group Tom Mason (Noah Wyle) went willingly with the aliens on one of their ships to free his son and learn their plans. Nobody has seen or heard anything from him during this time, and his absence has taken its toll on his sons. Ben and his older brother, Hal, have stepped up as fighters but quickly clash as they both seek to secure their roles as leaders in their father's absence. Many lives have been lost since Tom left, but the survivors of the 2nd Mass still struggle on with courage and resilience. In the first season, our heroes coped with the trauma of losing their world; this season, they take action and fight back.