Well,
kitty has already disappeared.
That was quick.
The food and water are untouched. Actually, that's not entirely true. There's a cricket in the kibble, and a couple of slugs in the water. Or maybe they're houseless snails.
Turns out there's a back exit from that corner. Fizzgig found it earlier - there are a couple of bricks missing in the wall in the bottom corner, leaving an escape route through the wall just large enough for the kitty to squeeze through.
Now we'll see if it
comes back.