Jeseni 1942 kapitan Hoffmann vodi podmornico U-612 na njeno krstno plovbo.

Aboard U-612, the men are adjusting to their new lives as a tense disagreement arises; in La Rochelle, Simone finds herself caught between Forster, mysterious Carla Monroe, and the entanglements her brother left behind.

Following a mission completion, the U-612 crew is reeling from a tragic death, adjusting to new passenger Samuel Greenwood, and witnessing further strain among the leadership; on land, Simone continues to uncover shocking discoveries.

The La Rochelle residents struggle to recover following an explosion, and Simone finds herself torn between alliances to Forster and Carla; on U-612, tensions are at a breaking point following a disastrous confrontation with the enemy.

As the crew celebrates the departure of one passenger, the reappearance of another is startling; on land, Carla tries to convince Simone that there are sacrifices to be made in the battle for power, and she starts to plot her next move.

Ujeti na U-612 imajo slabe možnosti; Simone se prilagodi dvojnemu življenju.