Related Clues:

• Peep
• Place bugs or wires
• Man of intelligence
• Cold War figure
• Austin Powers, e.g.
• Bond, for example
• George Smiley, e.g.
• One of Smiley's people
• Mata Hari, for one
• Secret agent
• Undercover sort
• Mole
• Tail, maybe
• Sight
• Kind of glass