The Land of the Leprechauns
Graham found an empty cavern leading south of where he fell. A little while later, the cavern turned west. It ended at a large door, but it was guarded by a giant, hungry rat. It had sounded like many little rats, but no, it was just one, and a big one.
Fortunately, Graham had swiped a piece of cheese from Dahlia's house earlier. He offered the cheese to the rat, which was definitely grateful for it, almost biting his fingers in his grab for it. After it disappeared through a wall, Graham entered the door.
Behind it, he found leprechauns!