Coraline moved into an apartment in an old house with her parents. There are other tenants in the old house and large grounds to explore.
When Coraline's parents were away she used the key to open the door that went to the empty flat and discovered her other home and her other parents.
In the other world Coraline has her other parents that are very creepy with button eyes and she interesting toys that come to life. Her other mother wants her to stay with them forever so she traps Coraline's real parents in a snow globe.
"It was a very old house - it had an attic under the roof and a cellar under the ground and an overgrown garden with huge old trees in it."
After beating her other mother in a game to find her parents and the three souls of the children Coraline was able to escape the other house. As she closes the door, she has trouble, but is able to shut it even when her other mother sticks her hand in the door.
It opened on to a dark hallway. The bricks had gone as if they'd never been there. There was a cold, musty smell coming though the open doorway: it smelled like something very old and very slow.
Back in the real world. The other mothers hand follows Coraline. The hand is trying to get the key to the other house back.
She looked a little like Coraline’s mother. Only...only her skin was white as paper. Only she was taller and thinner. Only her fingers were too long, and they never stopped moving, and her dark red fingernails were curved and sharp. "Coraline?" the woman said. "is that you?" And then she turned around. Her eyes were big black buttons.
Coraline finally defeats the hand and traps it and the key in the well. She is safe now and happy to go to school again.
There was a final moment of resistance, as if something were caught in the door, and then with a crash the wooden door banged closed.
She knew what it was, and she knew what it was after. She had seen it to many times in the last few days, reaching and clutching and snatching and popping blackbeetles obediently into the other mother's mouth. Five-footed, crimson nailed, the color of bone. It was the other mother's right hand.
Coraline counted under her breath. She got up to forty before she heard a muffled splash coming from a long way below.