On Poptropica Spy...

I need help with the spy island. I found 2 spies, but I need to find the last one and I don't know what to do and where to find him. Can someone help me?

ive done this island but cant remember
you can search on google: poptropica spy island walkthrough and you should find it

This is my favourite island!!

There's one on the roof of the headquarters, one at the docks, and then at Balding Avenue.

Thanks