Related Clues:

• Gumshoe
• Private eye
• Investigator
• Magnifying glass carrier, maybe
• Mr. Moto, e.g.
• Dick
• Detective
• One may follow a lead
• Satirical magazine
• ???
• Sherlock Holmes or Hercule Poirot
• Spade, for one
• Nicholson role in 'Chinatown'
• One on a trail, perhaps
• Whodunit character