As the excitement and anticipation of conflict slowly fades, the crew of U-96 is faced with an unforeseen enemy: boredom. The monotonous long stretches without action create tensions among the crew until a coded signal from U-32 presents an opportunity.
The Captain’s gamble against the Destroyer fails and exposes the crew to the horrors of depth charges. Despite surviving with serviceable damage, an outbreak of crabs and a three-week Atlantic storm test the limits of the occupants of U-96.
The crew's jubilation at sinking three ships is short-lived as they switch to silent running to avoid the British Destroyers using Sonar to find and attack them. Later, a triple encoded signal from headquarters interrupts their plans.