Related Clues:

• Gumshoe
• Private eye
• Shamus
• Sleuth, informally
• G-man
• P.I.
• Private eye, for short
• Magnifying glass carrier, maybe
• P.I., e.g.
• Mr. Moto, e.g.
• Dick
• Detective
• One may follow a lead
• Sleuth, for short
• Clue collector, slangily