Related Clues:

• Gumshoe
• Private eye
• Magnifying glass carrier, maybe
• Mr. Moto, e.g.
• Detective
• One may follow a lead
• Sherlock Holmes or Hercule Poirot
• One on a trail, perhaps
• Lead follower
• Olivier-Caine film classic
• Drew in books, e.g.?
• Sherlock Holmes, notably
• Magnifying glass carrier
• 48-Across, for one
• Sherlock