After the events of the first game, in which General Wilhelm "Deathshead" Strasse is eliminated, the Kreisau Circle retrieves the critically injured William "B.J." Blazkowicz from Deathshead's fortress before destroying it with a nuclear cannon. He. is still recovering from his wounds on a stolen U-boat called Eva’s Hammer.
Suddenly, the U-boat is attacked by Frau Engel, a sadistic Nazi commander and captures Caroline. Blazkowicz devises a plan to get himself captured and taken to Engel's airship, the Ausmerzer, which is suspending the U-boat above water. Engel tries to get her daughter Sigrun to decapitate Caroline, but the former refuses, resulting in Engel killing Caroline herself. Sigrun has a change of heart and tackles Engel, allowing Blazkowicz to use Caroline's armor. Blazkowicz disconnects Eva's Hammer from the Ausmerzer and flees back to the U-boat with Caroline's body.
Now armed with Caroline's armor, B.J is ready to return stateside, avenge his friends, kill every Nazi in sight and spark the second American Revolution.