Related Clues:

• Keep tabs (on)
• CIA worker
• Observe furtively
• Mole or plant
• Plant, perhaps
• Seek intelligence, in a way
• James Bond, for one
• Do some surveillance
• Bond, for instance
• Undercover agent
• Use a tap, perhaps
• Get a look at
• Smiley, Smart or Solo
• MI6 member
• Person with intelligence