Related Clues:

• 'Check this out!'
• Mole, maybe
• Bug someone, e.g.
• Catch a glimpse of
• Stratego piece
• ___-see
• Maxwell Smart, for one
• Watch covertly
• Look askance
• Snoop (on)
• Microfilmer, maybe
• Peek
• Visage
• Double agent
• CIA operative