Help! Prince Henry is injured!

I was in the middle of typing up my resume on my Royal KMM. I hit the return lever to go to the next line, and all of sudden everything just STOPPED. When I press a key, the type slug won’t go any higher than this:

And the space bar doesn’t do a thing at all. I tried fiddling with every setting I could find, no luck. I tried flipping the machine over to see if something had come lose, and couldn’t find anything. I know from cleaning that occasionally things get jammed up and that Henry really dislikes being upside down (I can sympathize) but this time even that didn’t free up whatever is blocked. Can anyone give me a hint as to where to look to find the problem?

ETA: So I sat down with a bowl of Reese’s Puffs, determined to fix whatever was wrong with Henry. Flipped him over again, and lo and behold, turning the caps lock on and off while in that position was all it took to fix whatever it was that was wrong. Behold the power of chocolate.