IN NARNIA A LION, A WITCH ANS A WARDROBE ,what problem had to face the characters?

The kids had to save Narnia from the White Whitch. She wanted the kids to go back to the wardrobe, but the beavers (I forgot their names!) told them Aslan needed them to fight for Narnia and in the end Aslan was killed and came back to life and he along with Susan and Lucy helped free Narnia from the White Whitch and they became kings and queens of Narnia!