Season3followsthefortunesofayoungU-boatcrewastheyengageintheBattleoftheAtlantic,arehunteddownbyanobsessedRoyalNavyCommander(RayStevenson)andaresentonadangerousmissiontotheSouthernHemisphere.TogethertheyformstrongpersonalalliancesunderthecommandofRobertEhrenberg(FranzDinda).　　AndyetEhrenberg'sthoughtsremaininKiel,wherehehasdevelopedfeelingsforGreta(ElisaSchlott).Theyoungmotherismarriedtoamanwhoisseriouslyinjuredandsufferingfromwarneurosis.AlsoinKiel,WilhelmHoffmann'sdaughterHannie(LuiseWolfram)istrappedinalovelessmarriagetoCommanderAlbrechtLessing(FlorianPanzner),abitter,emotionallydistantman.Hanniesuffersunderthetightconstraintsofherstatusandthesocialexpectationsthatgowithit.WhenshemeetsthecharmingsubmarinecommanderSchulz(PierreKiwitt),sheisplayingwithfire.　　MeanwhileintheexoticclimesofneutralLisbonwheretheexiles,spiesandcriminalsofEuroperubshoulderswitheachotherandtheirenemies,HagenForster(TomWlaschiha)discoversalethalplottostealafortuneinplunderedwartimegold.ThesediscoveriesandaspectsofhisownhistoryderivingfromdarkexperiencesontheEasternfront,leadhimtoquestionhisownactionsandmoralpath.TheyalsoleadhimtoashadowyfigurecaughtupinaconspiracythatmightchangethecourseoftheWar-forthebetter.Thatman,verymuchchangedbyhisownshatteringexperiences,isKlausHoffmann(RickOkon).Thesetwohistoricallybasedstrandscometogetherinanunexpected,thrillingfinale.