They Do It With Mirrors (Miss Marple)

When Miss Marple visits a girlhood friend she hasn't seen in 20 years, she finds that the friend and her husband have created a home for juvenile delinquents - and are living with 200 of them! Miss Marple senses danger, but not from the young people. Her fears are confirmed when a youth fires a revolver at the administrator and at that same moment in another part of the Victorian mansion a mysterious visitor, Mr. Gulbrandsen, is shot dead. Coincidence? Miss Marple thinks not. The suspense in this intricately plotted mystery builds as the clues point increasingly to a magician and his unusual mirrors.