A small town loose girl goes to the big city to work as a secretary, but soon starts to sell her charms and eventually becomes a full-time call girl.

Kirsten Kosinski leaves her provincial town to work in the big city. After getting a job as a secretary, she agrees, occasionally first and later on a regular basis, to sell her charms. Becoming a full-time prostitute, she thinks she could work independently, but quickly realizes that it's necessary to ensure the protection of a pimp to survive in this environment. A short attempt at living with a revolutionary group proves unsuccessful, and Kirsten resumes her activity as a prostitute. She strives to look to the future with optimism while waiting for the inevitable downfall. "The Butterfly" introduces European sensation Anna Kristina to American audiences in this sexploitation film with a thin veneer of social commentary, about the resume, dreams, experiences and memories of a "loose girl".