The first line of this book is so classic:
There was a boy called Eustace Clarence Scrubb, and he almost deserved it.
Eustace joins Edmund and Lucy in entering Narnia through a painting in Eustace’s room. Soon, they join an adventure with King Capsian X to find the 7 missing lords that had sailed from earlier times. The adventure introduces us to Reepicheep, the quite talkative mouse, and to a host of other memorable characters and lands along the way.
At one point, Eustace, a nasty little boy, becomes a dragon. To be healed, he must take off multiple layers of his dragon skin. He gets to a point where he can no longer take it off and Aslan must do the rest. After that, Lewis writes:
It would be nice, and fairly nearly true, to say that “from that time forth Eustace was a different boy.” To be strictly accurate, he began to be a different boy. He had relapses. There were still many days when he could be very tiresome. But most of those I shall not notice. The cure had begun.