I'm going off the rails on a Crazy Train

Every library has its "off" patrons, and mine is no different. We have a relatively small assortment of regular (as in visits regularly), odd-duck patrons who run the gamut from "quietly weird but doesn't bother anyone" to "annoying when the moon is full but essentially harmless." None of these people have ever caused me to feel alarmed, and at their worst, they simply require some extra one-on-one attention.

So, imagine my surprise when shouts of "KILL HIM! KILL HIM!" rang out from the back corner of non-fiction last night.

It started off quietly. I was pulling books for the holds list when I noticed some strange noise coming from one of the desks. It sounded like insane muttering, but it was fairly quiet, and I didn't think that anyone who wasn't standing right next to the source could hear it. The muttering turned into words, and then some sort of singing. It was still fairly quiet, but I poked my head around the shelf to take a look. There was one of my regulars - who had never uttered a peep before as far I as I knew - sitting there with a pair of headphones on. The headphones were blaring something that sounded like "church music" (for lack of a better description). I just assumed that she was engrossed in what she was listening to, and wasn't aware of her own voice. Again, since she was removed from the main part of the room, I didn't bug her about it.

Until it escalated.

Her volume grew louder, and her muttering became quite distinct - I was pretty sure I heard her say, "kill her." Several times. Hmmmmm. What to do. Now, I know that people who work in large and/or urban libraries have to deal with this kind of thing (and much worse) all the time, but here in land of the geriatric mystery reader, I wasn't sure what the protocol was.

I went to my boss and said, "One of our patrons is being a little strange. She's saying, 'kill her' over and over again. It's getting louder. Um, do we have a specific way we should handle this?"
My boss said, "Tell (the Director)."

Eventually, (the Director) came over to check out the situation. By this time, the patron was in a full-on shouting chant of "Kill Him!" and the other patrons were looking around with faces that clearly said, "WTF?" She approached the woman and asked if she "needed help." The patron said, "Oh, can you hear me!? I'm sorry! I'm having a difficult time right now, and I'm praying." She quieted down, and we determined that she was (most likely) harmless. Poor dear.

I went back to my desk and Googled "kill him" +prayer, but somehow I don't think she was listening to Shellac. In fact, when I went back to check on her later, I could hear the Star Spangled Banner blaring in her headphones while she (quietly) muttered, "You can't fool me, oh no you can't." Heh.