Hitler Youth tells the story of the Hitlerjugend, which was formed to indoctrinate German youths with respect to the policies and beliefs of Adolf Hitler and Nazism. The Hitler Youth became an important part of the Nazi war effort.

The Hitler Youth was started as early as 1922. Hitler made political use of the organization in 1932, when a Hitler Youth named Herbert Norkus was stabbed to death by a Communist youth group. Hitler played up public sympathies, and Norkus' death helped to sweep Nazis into parliament in elections of that year.

The Hitler Youth was soon made a compulsory part of a young German's education, with girls joining the Bund Deutscher Madel (BDM), or League of German Girls, the female branch of the Hitler Youth. Boys and girls excited at the chance to serve their country, play sports, and go camping soon learned that the Hitler Youth experience was one of drudgery and unquestioned discipline. While some became disillusioned, most fully embraced the program and swore unquestioned alliance to Hitler. The Hitler Youth were known as some of the fiercest and most fanatical advocates of Nazism. Hitler himself recognized the advantage of instilling Nazi virtues into children as young as possible.

By the late 1930s, Hitler Youth had evolved into a paramilitary organization with the purpose of training young people to join a branch of the German military. Boys joined the Wehrmacht (German army), Luftwaffe (air force), or navy. Especially promising youngsters were invited to join the SS, Hitler's brutal personal army. Around this time, Hitler played to the anti-Semitism of the German people, and Jews were persecuted and either forced out of the country or brought to concentration camps to labor and eventually be executed. The majority of German people had little idea the Holocaust was occurring, due to strict censorship.

In the later part of the war, the Hitler Youth got its own soldier division, the SS-HJ, which fought at Normandy and later the Battle of the Bulge.

Not everyone bought into the lies of the Nazis, and the book chronicles some former Hitler Youth teenagers who fought to bring the truth to the German people. This included Hans and Sophie Scholl, members of the White Rose resistance group at the University of Munich, and Helmuth Hubener, who spread anti-Nazi leaflets. These people were beheaded for their treasonous behavior.

As Germany was invaded by the Russians and Allies at the end of the war, members of Hitler Youth fought until the bitter end, using underground tunnels to conduct sabotage, and dying in vain while trying to stop the Russians at Pichelsdorf Bridge. At the conclusion of the war, Hitler Youths were made to visit concentration camps and witness the horrors of the Holocaust. The Hitler Youth had to live with themselves for having helped a mass murderer kill millions of people.