The town citizens are convinced that Nick is in town to solve a case and all the denials from both him and Nora only deepen their conviction. However, Nora's purchase of an old painting provides the means for the pair to become involved in a murder mystery with complications involving an abandoned baby, a spy ring, and a childhood rivalry gone awry. Eventually, Dr. Charles sees how special Nick's talents are and the movie ends on a high note with him finally respecting the talents of his offspring.
The background that the movie provides for Nick is rather interesting as it is totally at odds with what is revealed in the book by Dashiell Hammett. In the book, Nick is of Greek origin from a father who changed his surname from Charalambides to Charles to fit a photograph. The type of small town upbringing which is portrayed in the movie is seemingly at odds with the characterization in the book.