It’s a movie I saw when I was 3-7 (late 1990s) about this group of adults who kidnap children and keep them in the pipes or sewage system or something underground. I don’t completely remember the plot but I know there’s an evil woman who punishes the kids and they’re all trying to escape. Also there’s a lot of green slime in the movie so it’s a kind of humorous but scary kids movie. Please help!!