I'd argue that someone phoning in such an over-the-top movie scenario threat from an anonymous phone number is also not a "credible and imminent threat of viole

I'd argue that someone phoning in such an over-the-top movie scenario threat from an anonymous phone number is also not a "credible and imminent threat of violence". Definitely something that warrants investigation of course, but not something to start pulling out all the guns and start shooting people when they open the front door to see what all the ruckus is about.