Nancy is asked to solve two cases. The first mystery concerns a valuable collection of rare books. Wealthy Mrs. Merriam has commissioned a supposedly reputable art dealer to sell the collection, but she suspects the man is a swindler. The second case involves the baffling theft of a beautiful marble statue. The unusual statue, which is known to whisper, bears an uncanny likeness to Nancy.

The story is based on the original title of the same name first published in 1937. The plot is vastly different in this extensively revised and shortened version.