The Japanese Ninja Surprise is an installment in the long-running Flat Stanley series, following the adventures of Stanley Lambchop, a boy who was accidentally flattened and can now travel the world by being mailed in an envelope. In this adventure, Stanley is likely mailed to Japan, where he becomes involved in a mystery or adventure centered on ninja culture. The story uses Stanley's unique flat state for humorous and inventive problem-solving. The book is a fun, educational read that promotes themes of travel, cultural awareness, and creative thinking