She was a single woman who was raped and killed by Roger Hicks, her car dealer.
Ann went to Roger in hopes of buying a new car. Roger ran a background check but sent her to another dealer. However, he had learned what he needed to know in preparation to kill her. Roger went to Ann's house, talked his way inside, and then raped and killed her.
Dexter was called to the crime scene. He decided to investigate the murder on his own and confirmed that Roger had killed another woman, Lynn Hall, a month earlier.
Dexter later killed Roger in Ann's home.