Plot hole: Carol and Duncan escape out the back of the shop - but there are no police waiting for them, which makes no sense at all. In reality, with such a situation, the police would have been waiting at the back door. There seems to be no one around at all, as they were able to dash through an apartment. When they finally do run into a cop, he automatically assumes that Carol is an innocent bystander, and not one of the robbers. He couldn't have known this, and in reality, a policeman wouldn't assume it.