How to reset mac display arrangement?

The multiple monitors attached to my early 2015 13" MacBook pro running Sierra (10.12.5). Yesterday, while rearranging them in the system preferences, one of them got severely misplaced, such that I no longer can see any displays in the system preferences panel. As a result, I can not fix the problem.

QUESTION: Where is the display arrangement information stored, and (if it isn't self explanatory) how do I reset it?

MORE DETAILS

Yesterday, I was resetting my display positions in the system preferences (I have two external monitors in addition to the built in one). I got distracted at the last minute by a coworker, and later I realized something strange had happened. My system preferences/display settings now looks like this:

You'll note that NO monitors are showing up. At first I thought "oh, somehow I triggered a bug and it just doesn't show the monitors". However, more investigation showed me I could not get my mouse onto the third monitor. It didn't seem adjacent to either of the other monitors.

I then noticed that if I minimized and maximized on of the windows stranded on that inaccessible screen, the genie effect seemed to indicate that the position of the monitor was waaaay far down compared to the other monitors. That is, you know how the shape and direction of the genie effect seems to show where the window is placed relative to the dock. So, my impression is that my screen arrangement is actually like this (the red rectangles imply where I think the screens are, relatively, though, I think they're actually much further apart than this implies)

I tried creating another account and then using a terminal shell to go in and nuke all my Library/Preferences, in hopes the display settings were in one of those files, but of course then realized this setting is across all accounts. So, that didn't work. I tried resetting the NVRam (pram!) and starting up in safe mode... but this all had no effect.

SOOOO, I'm trying to figure out where this data is stashed so I can just reset the screen arrangement from scratch.