OK Rebecca, this sounds SO MUCH like my story - except mine was January 2012 and the thing grabbed my arm, not my hand. I actually was starting to think we were on the same ride! My first response was to try and stand up, but you know you can't on ToT, so I screamed (along with everyone else) while grabbing it with my hand and throwing it as hard as I could without cocking my hand back. I actually thought I might have just tossed it on to someone else.
Man, I'm glad I don't know what it was. Because it certainly didn't feel like a mouse (and I've handled quite a few of those). But it was awful grippy.
Well, you know... Those people who went up in the elevator many years ago, on an evening very much like the one we have just witnessed- Probably haunt the elevator. Grabbing people is the only way they get their kicks!
My money is on the nanny- she looks mean!