When the case of two girls murdering a younger boy showed up in the English court Mary Bell was called a "Devil" and "Svengali" (from George du Mauriers novel Trilby, an evil person). She was an evil person and had to be punished for her deeds.
    With the book "The Case of Mary Bell" Gitty Sereny tries to find out and explain why Mary or maybe the both girls together did what they did. It was a "cry for help" as Sereny puts it. A cry for help which the adult surrounding ignored, not only once but several times. The book mostly handles the case of Mary Bell. Later has the section of the two ten year old Liverpool boys murdering a six year old been added to the book as well.

Sereny criticizes the way the English authority handled the case of Mary Bell and rises questions as "Can a child be born evil?", "Why does a child kill?" and "Is it right to threat and punish a child by the measures of the adult world?"
    The book may be painful criticism towards the English authority, but also an eye-opener not only for England, but also for the rest of us. Mary Bell was in no way unique and if we do not act in time it will happen again.
    A child who kills does not do this by evil. A child who kills has different standards and ways of seeing things.