Scary monsters in tunnels

I had a pretty weird dream last night. I was watching this scary movie and it was about this hole/tunnel in the earth that had a bunch of scary monsters living inside, and some of them were pretty creepy looking. And some lady went down inside of it and was like making new openings for them to be leaked into our world. But by the end of my dream, the movie kinda turned into like Flushed away and there was talking snails and slugs and bugs