Then I look around the bed and realize Vader is missing. I call out, "Vader?"
I hear, "Thump. Thump thump."
I call again, "VADER?"
"Thump."
Apparently he had jumped up onto my 3 foot high book shelf that is placed facing out from a corner. He somehow fell behind the bookshelf to the floor (or maybe decided to jump down there) and was trapped in the small triangle shaped space between the back of the book shelf and the corner. The thumping was his attempts at leaping back up but then falling back down to the floor.
I had to jump out of bed and rescue my little kitty. I moved the bookshelf out of the way and he walked back to bed.