A rookie cop and his girlfriend's uncle, a police captain, disagree on the methods that should be used to catch criminals.

Lloyd Wilson, trusted employee of an investment firm, is suspected of theft when $20,000 in security bonds is stolen from his office. Tarzan, the Famous Police Dog, has an intuitive dislike of an apparently respectable citizen, and this leads Wilson and the police to the gang headquarters. Tarzan wins a public citation for his leading part in breaking the case against a desperate gang of criminals.

Scotland Yard is called in when the effigy used in a Guy Fawkes Day celebration turns out to be the burned corpse of a real man.

How the X-ray works and its use in police work, surgery, industrial engineering and automobile manufacturing.