Nah, I am not in to espionage.

My son will be 10 end of this month and I have to organize a surprise birthday party.
As usual my main concern is the cost.
As much fun for as little money = one happy child + one happy mama.
So I decided to have a Spy themed party.
So far I haven’t got any ideas as to how to host such a party.
Have you ever hosted a spy themed party? Any ideas?