They Do It with Mirrors

The title is the key to the book: Christie builds the mystery around the idea of a stage illusion, where the audience sees only what it is meant to see. The central scene, in which a quarrel holds everyone's attention while something else happens, is a lovely piece of plotting, and the solution is satisfying once the trick is revealed.

Stonygates itself is an interesting setting, part family home and part reform project, and Christie uses it to explore the gap between grand ideals and everyday kindness. Carrie Louise, gentle and seemingly unworldly, is at the centre of everyone's concern, and Miss Marple's long friendship with her gives the story a personal note.

The large cast can be hard to keep straight at first, and the young offenders are drawn mostly as types. Some readers find the middle section talky. It is also published in the US as Murder with Mirrors, so check before buying a second copy. As a clean, clever puzzle with a strong central trick, it is a fine choice. About 224 pages in the William Morrow paperback.