Last night I actually SAW the culprit. Squatting down on the roof of the neighbor's house, just outside my upstairs hall window, looking for all the world as if she were expecting me to hand goodies out to her.
Fortunately, her choice of wearing apparel gave her away. Had she been all in black, I probably would have missed her, especially if she'd closed her eyes - but the whispy grey was ghostly, shining in the darkness.
Yes - it was the Illegal Alien Kitteh. Finally spotted. This time not at the window in the livingroom where it had torn the crap out of screens (the new anti-pet screening seems to be working) - but on top of the neighbor's roof. I hissed at it. She scooted back a few steps, but kept looking at the window. I hissed again, louder and raised my hand... she scampered off. I closed the window down over the screen.
This morning there are 2 small holes in the screen. I have put a spray bottle of CleanUp on the windowsill. Fucking cat comes back, it will get a face full of Chlorox.
I am NOT happy with this little housebreaker.