- ISBN: 0807576042, 9780807576045
- Page count: 128
- Published: 2009-03-01
- Format: Paperback
- Publisher: Oasis Audio
- Author: Gertrude Chandler Warner
When the Boxcar Children visit a neighbor's house, a mysterious old wedding photo and a riddle lead them on a "spy game" devised long ago by the original owner of the house. When the children hunt for clues they discover amazing things, like a stone path whose pieces fit together into a jigsaw puzzle But soon the children begin to suspect that there's a mystery inside the mystery. They read about a similar puzzle in one of their new Detective Club books, and they meet a woman who looks eerily like the bride in the old wedding photo. Just who is behind this spy game?