Not bad for a first fic. I did notice a slight discrepancy. Just before the robbers enter Dunder Mifflin Jim told Pam to call the "pick up." I think you meant to say police there since when Dwight shows up at the station the cops are getting ready to head out. So there's that.

One of my favorite authors once described writing as, "painting a picture with words." The dialogue here is pretty good. If you add in some more description of what's going on it would help flesh out this story a lot.

For instance writing something like, "Are you implying that I can't shoot? Because you'll regret it when I...," Michael said as he raised the blunderbuss to his shoulder and pulled the trigger. A large cloud of white smoke billowed from the barrel of the gun as Michael started hopping around clutching his shoulder. "MY ARM!! MY ARM!!" Something like that adds a bit more detail to the scene. Hope that helps for your future writing.

Author's Response:

Thank you, warrior4! :)

I guess the first problem is part of the second: in my mind, Jim asked her to call the guy who would pick up the documents, for he was not worried about the noise (offering to go check it by himself and all... I might be wrong for not having watched it all, but I don't see him as the brave guy on the frontline), but Pam ended up calling the police, and only Angela noticed. The lack of description might have even affected the understanding.