On Halloween night, while peering into the Oleson's windows instead of soaping them, Laura witnesses something gruesome. And what is more frighten to Laura is no one believes her about what she witnessed except Carl Sanderson. Together these two try to solve the mystery of what happened to Harriet Oleson.  Devilish fun ensues ...as much as it can out on the Prairie.  Will Laura consider a future as a detective in homicide? What other meals does Mr. Oleson know how to cook? Again, should I be concerned about Carl Sanderson?