Oxford Bookworms Library 1: Shirley Homes and the Cyber Thief

Shirley Homes, private investigator. Like Sherlock Holmes a hundred years ago, she lives in London, enjoys working on difficult cases, and has some helpful friends. She understands people, is a good listener, and of course, she is clever with computers.
 In today's world that is important, because a lot of crime is cyber crime. In this second Shirley Homes detective story, Shirley must catch a cyber thief. But how? You can't see a cyber thief, you can't hear a cyber thief.
 Only the computer knows, and the computer isn't talking ...