Sometimes a character shows up and he won’t leave. No matter how much you turn back to the script, he won’t go. He runs riot in your perfectly planned plot. He sneers at your carefully manicured characterization, he laughs in the face of your protests.
What this gatecrasher does is grab that plot by the nape of the neck and shake it up good. It was never really a party until he showed up.
This is what happened with Special Agent Benny Reza, just a nice Jewish-Persian boy from Tehrangeles.
Image courtesy of The FBI