LitCharts assigns a color and icon to each theme in The Book Thief, which you can use to track the themes throughout the work.
Death
Words and Language
Books
Stealing and Giving
Color, Beauty, and Ugliness
Summary
Analysis
Liesel and Rudy return to apple-thieving, but the old gang has a rich, charismatic new leader named Viktor Chemmel. He mocks the two but allows them in the group. Liesel and Rudy immediately dislike the tyrannical Viktor, and when Rudy complains about the slim pickings, Viktor chokes him. Rudy and Liesel leave the gang, but as they walk away Rudy spits at Viktor's feet, and Viktor swears revenge.
Like Franz Deutscher, Viktor Chemmel is another unsympathetic young character who abuses power. The fun and seemingly innocent apple-stealing has changed now into something more ominous – another example of how someone like Hitler could rise to power through charisma.