The end of Wolfenstein: Youngblood takes the series in what is potentially a very exciting new direction. Spoiler warning…
Now, let’s dig in.
Twin sisters Jessica and Sophia Blazkowicz, daughter of the series’ iconic protagonist B.J. Blazkowitz, spend most of their time in Youngblood looking for their missing father. At the same time, they help the French Resistance in a Nazi-occupied Paris to get rid of the Nazis who have still occupied the country since World War 2.
Two of these French Resistance members are Juju and Jacques, who act as your comrades throughout most of the game. However, once you’ve hacked all the main computers in several nazi towers – your initial goal in Youngblood – their true nature is revealed.
Source: IGN.com Wolfenstein: Youngblood Ending Explained