He wasn’t the same character as the one in the book, he’s better. The book version was very extroverted and physical, he’s practically dancing the first time we see him. But Wilder delivered a more internal performance, more mysterious and subtle. With that deadpan delivery and the twinkle in his eye, you can never quite tell what he’s thinking. He never reveals exactly what’s going on inside until the end. I find that way more believable and compelling. He will be beloved by many generations to come.