How is this possible ?

After Max got the permission to carry out his plan, he immediately put it into action and instructed everyone their roles. But first of all, instead of sealing off the passage as one would expect, Max decided to leave it as it is and even restored it to how it was before they found it. Although there is a high chance that the real behind the scenes person already knows about this, but you have to at least maintain the front. 

"Inspector Jolly, we are going to set up a trap for the robbers. They are going to do it tonight right? Then we'll be waiting for them. "

Max said seriously. 

"But what if they don't come? "

Inspector Jolly asked hesitantly. 

"Well then we can only say that luck is not on our side. But they will definitely come."

Max said vaguely. 

"Alright detective Max, tell me what I have to do? "

Inspector Jolly asked with a solemn look.