This was a game in which you had to remove the plastic people from the mouth of a purple people eater.
It worked in much the same way as Operation, in that you used metal pliers to extract people from the monsters metal-lined mouth.
I had this and played it quite a bit, but after a few days it was decided by my parents that it should be kept at my grandads house, due to the fact that it gave me really bad nightmares.
(So just to recap, my parents, upon noticing that I was no longer sleeping peacefully at night, decided to NOT throw it away completely, but just control my access to it. Sort of in a "break him in gently" tactic. I no longer feared going to bed at night, but feared going to Grandads...)