Korinna is a 13-year-old German girl and an enthusiastic member of her local Nazi youth group, the jungmädel. Deeply loyal to her country, she initially believes wholeheartedly in the government's propaganda and the superiority of her race. Her worldview faces a severe test when she discovers a terrible secret hidden inside her own bedroom.

Rita is Korinna's best friend and a strict adherent to the Nazi regime. She embraces the youth group teachings without hesitation and actively looks for suspicious behavior in others. Her loyalty to the state supersedes her loyalty to her friends and family.

Korinna's mother is a perceptive woman who outwardly conforms to the expectations of German society while quietly harboring dissenting beliefs. She carefully tries to guide her daughter away from hateful ideologies. She takes immense risks to do what she believes is right and feeds those hiding in her home.

Rachel is a five-year-old Jewish girl forced into hiding to escape persecution. Bored and confined to a small dark space, she maintains a cheerful exuberance. She finds joy in drawing pictures of her old home and playing with a small kitten.

Eva is a friend of Korinna and Rita who struggles to conceal her sympathy for others. Unlike her peers, she quietly questions the cruelty required to build a strong nation and shows visible distress when people in her community are hurt.

Korinna's father is a schoolteacher who acts as a quiet but firm opponent of the regime. He often uses the alley behind their house and attends mysterious late-night meetings, working with an underground network to smuggle persecuted citizens to safety.

Sophie is a Jewish mother living in constant fear behind a wardrobe in the Rehme home. She endures dark, airless conditions to protect her young daughter and relies entirely on the Rehmes for food and safety.

Hans is Rita's older brother and a Gestapo officer. He conducts raids on homes searching for hidden Jewish citizens and actively enforces the regime's violent policies with enthusiasm.

Sophie's husband and Rachel's father, who spends the early part of the story hiding in a cold barn elsewhere in the city. He is separated from his wife and youngest daughter for their mutual safety.

The older daughter of the Krugmann family. She hides in a barn with her father while her mother and younger sister hide at the Rehme house.

The local neighborhood butcher who used to give hard candies to Korinna. He is publicly arrested in the street for being a sympathizer.

A teacher at the girls' school who openly expresses frustration about pasting pages of their history books together. This action makes her a target for the authorities.

A small kitten brought into the Rehme home. He frequently slips into the hidden space behind the wall, becoming a source of comfort for young Rachel.

Frau Rehme's best friend. She shares similar dissenting views and is eventually targeted by the authorities for her involvement in hiding Jewish citizens.

Rita's cousin who privately expresses that the treatment of Jewish people is a sin, prompting Rita to consider reporting her.