I haven't seen 13 Days, aj, so I don't know. A good example of the accent is Good Will Hunting. At least Matt Damon and Ben Affleck are from here.
I've had people say to me when they first meet me "Wow, you don't sound like a Kennedy". Umm, yeah they're a breed unto themselves. I actually don't have an accent, though, so if you ever meet me aj, I won't sound like your NH boy, even though I grew up in NH.