Where I chapter by chapter review the book versus the movie. Some differences are minor, while sometimes entire stories were jettisoned from the films, which is why I encourage people to read the books even though the films were quite good.
This first book is shorter than the rest in the series. The main things missing are more depth to the characters and story. There aren’t side stories completely jettisoned, like Hermoine’s creation of S.P.E.W. and the whole house-elf debate. Of all the films, I think this first one was closest to its source material. What was left out of this chapter in adapting it to the screen didn’t hurt the overall story.
The film opens with Dumbledore, Professor McGonagall, and Hagrid leaving Harry with the Dursleys deep in the night. We never actually see the Dursleys discover the boy on their doorstep or their reactions.
Mr. Dursley leaves for work and sees a strange tabby cat on the corner (McGonagall). At first, he thinks the cat is reading a map. As he’s driving to work he sees many people in his town dressed strangely; wearing cloaks. There are owls swooping past his window at work, although he doesn’t see them. When he goes out to get doughnuts for lunch, he overhears the strange people in cloaks talking about the Potters, which is his wife’s sister and family. Mrs. Dursley is described as “thin and blonde”. In the film she has dark hair.
The Wizarding World is out and about because Voldemort was defeated. Mr. Dursley is hugged by one of them on his way home. He knows something is going on – even the news he watches talks about owls and shooting stars. When he questions his wife about it, she bristles at the thought of hearing from her sister. Before he goes to be, he looks out of the window and sees the same tabby cat he saw earlier watching the house.
While the Dursleys are asleep, something similar to the beginning of the movie takes place. Dumbledore arrives and greets the cat, knowing it is Professor McGonagall. She is sharply critical of the celebrations that have been happening, knowing that the muggles have noticed it, although Dumbledore chuckles at her concern. She does not know for sure at this point that Lily and James Potter are dead – she has only heard rumors.
There’s a good deal more depth to the idea of sending Harry to live with the Dursleys. Dumbledore feels it is the best place for him; away from the celebrity and notoriety the rumors have generated for the baby.
“Hagrid,” said Dumbledore, sounding relieved. “At last. And where did you get that motorcycle?”
“Borrowed it, Professor Dumbledore, sir,” said the giant, climbing carefully off the motorcycle as he spoke. “Young Sirius Black lent it to me. I’ve got him, sir.”
Jumping ahead at the mention of Sirius Black – it’s obvious at this point he is still considered a friend of the Order of the Phoenix and not the one responsible for the betrayal of the Potters to Voldemort.
Hagrid lets off a howl at the thought of leaving baby Harry with the Dursleys and McGonagall scolds him that he’ll wake the muggles who are now sleeping.
One small hand closed on the letter beside him and he slept on, not knowing he was special, not knowing he was famous, not knowing he would be woken in a few hours’ time by Mrs. Dursley’s scream as she opened the front door to put out the milk bottles, nor that he would spend the next few weeks being prodded and pinched by his cousin Dudley…
He couldn’t know that at this very moment, people meeting in secret all over the country were holding up their glasses and saying in hushed voices: “To Harry Potter — the boy who lived!”
In the movie we miss the background on the Dursleys and their seemingly “normal” life and how the magical world is bleeding into the muggle world with the celebration that Voldemort has been defeated. We see a little more of McGonagall watching the Dursley home and what leads her to the conclusion that they aren’t great people to leave with a baby who is considered a hero .