Sue Swanson, a self-employed scientific consultant living in Germany, is frustrated with her life. For lack of work, she seeks an occupation to keep herself busy, and applies for an unusual job at a pharmaceutical company. When she discovers that some of the medicines produced on site appear to be faulty, she loses the job, but the director demands her services back in an even more unusual manner. Not knowing whether she can trust him, she decides to accept his request to investigate under cover. Soon, more irregularities become apparent, and when the first victim presents itself, Sue is determined to get to the bottom of it