The film tells the story of Rodney Alcala, a convicted serial killer believed to be responsible for over 130 murders.

In 1971, he is caught after having raped and beaten 8-year-old Rosie Hoffman, but because her parents move her to Mexico, she does not testify at Alcala's trial, and he is charged only with assault.

He is repeatedly charged with abusing girls, but his good behavior and kind manners gain him preferable treatment and light sentences.

Alcala is ultimately identified by a park ranger who saw him walking with a murder victim named Tammy Jensen days before her body was discovered at the same location.

This conviction is overturned in 1984 due to the prosecution's reference to Alcala's previous crimes causing bias in the jury, but he is retried and sentenced to death again in 1986.