Katja Bienert recalls as her mother Evelyn, who did her management, arranged a meeting with production-assistant Otto Retzer in the Kempinski in Berlin: The famous producer Carl Spiehs was hiding behind a newspaper taking a glance at her and decided without casting to give me the responsible main part Petra. "When we where shooting in summer 1978 I was 11 years old, looking like a sixteen-year-old, which made the harmless nude scenes delicate. As I looked like a grown-up already at the age of eleven, taking off the cloths was like a freeing therapy." She said she was full of complexes over her early-blooming voluptuous body, but she was already used to being nude in front of people. She had already posing nude for photographers Lutz Stark and Jim Rakete. Even at that young age, she could see that men were attracted to her.