Related Clues:

• Expression of surprise, satisfaction or triumph
• Surprise, surprise! That's what makes the medical officer turn up in Nebraska.
• Pleased with the expression that might get one the O.M. in the States
• Either way, the triumphant express
• Bit more to make this usually triumphant
• They did theme to "The Living Daylights"
• Code cracker's cry
• What a teacher likes to hear from a pupil
• Exclamation akin to 17-Down
• "Surprise!"
• Cry of satisfaction
• ''Thought so!''
• Cry when a light goes on
• 'The penny drops!'
• Word of discovery