Season: 1

Pacifists endanger themselves by leaving the relative safety of Sidonia, while the enemy shows up larger and fiercer than before.

The Gauna find a distressing way to demoralize and out-fight the attack force. Nagate returns to Sidonia with a prize that may help in the fight.

Nagate is blamed for a defeat and harbors guilt over a casualty; the early years of Sidonia are revealed.

The enemy is revealed to be even larger and deadlier than previously believed, resulting in three squads engaging in a deadly fight.