Bill looks a lot like I Should Have Stayed in Bed Sam (1965), and he has his off day too. A cryptic collection of numbers had been substituted for his homework paper. His friend Ken Noonan helped him reenact the events surrounding the crime--which turned out to have been caused by the one source they had both been avoiding, Ken's troublesome younger sister. Bill and Ken are the sorts of detectives who think instead of act, which slows down the appeal of this book for young readers. That inadvertently insidious sibling provides fun, however, and so do Syd Hoff's well-known cartoon drawings.