Easter Egg Hunt 2012 - Problem Four

Spy

Albert, Bertha and Cedric are spies. One of them is a double agent. This is what they say when they are questioned:
Albert says “Bertha is a double agent”
Bertha says “ Cedric is a double agent”
Cedric says “Bertha is lying”
The double agent is lying, the other two are telling the truth.

Who is the double agent?

 

What is the Easter egg hunt?

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