I tend to cringe at any major departures from the original story when a book is adapted for film, but that's just me — and I guess it really depends on how much any new characters are in keeping with the spirit of the story, and whether they play a really good and interesting role in the plot or seem to be just there to pad out the story or to make up the numbers (of female characters, or ethnic minority characters, or whatever else). For example, the fox in the film of LWW, and the subplot attached to him, just seemed to me to be a distraction from the main plot and a pretty redundant addition overall.

One thing I wouldn't mind (provided it's done well!) would be if Netflix could take characters that are mentioned in the books but don't really feature in the plot, or who only come in very briefly, and expand on them. Just some ideas off the top of my head, taking the books in chronological order (which isn't my preference for reading, but it's what I would guess Netflix may be most likely to do)...

MN — Could we have scenes in flashback involving Mrs Lefay and what Uncle Andrew learned from her? Jadis and her sister and something of the relationship between them, and how it evolved (or devolved) into war? Frank and Helen and their life at home in London? (I've got a "head canon" idea for a scene between them early on in the story to introduce them to viewers and flesh their characters out a little bit, but that would be something for another discussion.)

LWW — Harder to think of additional or expanded characters for this one because it's got the simplest plot with the fewest hints or name-drops of other characters! I once saw a stage version that added in other Talking Beasts, apart from the Beavers, who were part of the "underground resistance" against the White Witch and who communicated with each other to pass on details of the Pevensie children's progress on their journey and to send the Beavers to find and meet them. And of course there's the little party of revellers that the Witch turns into stone — Lewis stated privately, in letters to young readers who were asking what happened to them, that of course Aslan brought them back to life, but he admitted he should have said so in the book. Maybe we could see some more of those creatures somehow and get to know them, so that we really feel for them personally when they're turned to stone, and then yes, we should get to see Aslan restoring them as well!

HHB — I really like your idea, Jasmine, that we could meet Bree's and/or Hwin's future love interests — we're simply told at the end that they both got married "but not to each other", so it would be interesting to expand the cast of Talking Horses a bit further. Perhaps we could see what happens when Bree does meet others of his own kind and is desperately trying to make himself look proper and dignified, and it turns out Narnian Talking Horses all LOVE rolling in the grass (the very thing Bree loves doing but is terrified that it's a lowly habit he's picked up from ordinary horses) and are totally unfazed by his messily trimmed tail and they all just completely puncture his air of superiority, in humorous ways. I can imagine getting some comedy mileage out of that! And I personally would love for Hwin to meet a gentle, kindly, warm-hearted stallion who understands her shyness and nervousness and helps her to flourish as a character far more than Bree could have.

PC — Maybe Gwendolen and/or the young schoolteacher, both of whom are rescued by Aslan and the romping revellers, could have their roles expanded a bit somehow and do some more in the story? Or we could get to meet some of the other Telmarines, especially the younger ones, who come to love the Old Narnians and support their return? Not early in the story, as we need the tension of Caspian being on his own at first and feeling like he's (almost) the only one who cares about the old times, but later on, maybe we could have scenes in Miraz's army that show some of his followers being deeply uncomfortable with his whole regime and secretly wanting the Old Narnians to win. That then brings us to the point at the end where some of the Telmarines agree to Aslan's offer to send them to our world, where their ancestors came from, but others are happy to stay and support Caspian in his rule. It'd be good to expand on that situation.

VDT — One thing that intrigues me is that we're told the Chief Dufflepud has a daughter named Clipsie who originally said the spell to make them all invisible. Maybe that scene could be rewritten so that the Chief demands that Lucy should find the Magician's book and read the spell to make them visible again, but he refuses to give any real details and Lucy goes off in despair, wondering what to do, but then Clipsie goes to her privately (invisible herself, of course) and tells her exactly where to find the book? Then when they do become visible again, we could have another scene where Clipsie comes up to Lucy to thank her. There could also be something more made of the Sea People they see much later in the voyage, or other characters from the Lone Islands (Lord Bern's wife and children, perhaps?) playing a larger role in that part of the story.

SC — Not quite so much springs to mind for this one, as it's rather a lonely journey that the two children and Puddleglum make and that's a big point of the story. It'd be nice to get to know some of the Earth-men better (and surely there are women among them too?), but we don't really have the chance, as they aren't freed from the Witch's mind-control until she dies, and then as soon as she does, her entire underground world starts to crumble and we do need that fast-mounting tension as our heroes race against time to find the way out. I'd love a glimpse of Bism and some of the creatures that live there, but that's another point of the story, that we DON'T get to see it because Rilian needs to successfully resist that temptation!

LB — This is also a very lonely adventure for a lot of the way and there needs to be the sense that the good characters are getting more and more isolated as Narnia is overrun by the forces of evil. I'm having trouble thinking of any barely-mentioned characters that could be usefully expanded on, or any point in particular where new characters could enhance the plot without dragging it off track. Maybe others here will have some ideas?

@courtenay 

I think you kind of have to accept that Netflix are going to make some changes. As long as it's not too distracting, I think it's fine. As long as they don't botch the story line (looking at you Walden's Voyage of the Dawn Treader!) We can even have a whole discussion in another thread about what changes from Walden we've liked and what we didn't like, and what Netflix could do to improve.

As for adding new characters, as long as it works within the universe. Hey, as long they don't add the Green Mist again in Voyage of the Dawn Treader. There could possibly be canon characters and original characters.

We could probably see more marsh wiggles in The Silver Chair besides Puddleglum. I kind of thought of what if Puddleglum's father was on the Dawn Treader.

Maybe in The Last Battle, they could give the boar and the bear each a name. They could even give the other dwarfs besides Poggin, Griffle, and Diggle each a name. Hey, maybe they could name Emeth's six brothers. It's possible they were in the Calormene army as well, serving under Rishda. I think a way to expand on Emeth is to make him sympathetic.

Another I thought of was what if Archenland was given a bigger role? They only play a major part in The Horse And His Boy. They are mentioned in Prince Caspian, The Silver Chair, and The Last Battle. They don't seem to get enough attention.

Why not just stay accurate to the books? What's the point of adding characters, not in the novels? 

Posted by: @jewel

Why not just stay accurate to the books? What's the point of adding characters, not in the novels? 

I would like Narnia movies to stay accurate to the books, but it's not that easy. As I've mentioned before, I don't think you can do it word for word from book to screen.

They could easily name Emeth's six brothers in The Last Battle. They could have been soldiers as well (I don't know if they've went to Narnia under the command of Rishda like Emeth did or if they were among the new soldiers at Cair Paravel).

Posted by: @jasmine_tarkheena

They could easily name Emeth's six brothers in The Last Battle. They could have been soldiers as well

Wouldn't that just make the story overlong and needlessly complicated? 

Posted by: @col-klink

Posted by: @jasmine_tarkheena

They could easily name Emeth's six brothers in The Last Battle. They could have been soldiers as well

Wouldn't that just make the story overlong and needlessly complicated? 

Well, The Last Battle has a really complicated plot as a whole. They could even give Emeth more of a character development. We might see his reaction when he discovers that Rishda doesn't believe in Tash or any of the supernatural.

It's worth noting that it costs money for extra characters. It means casting extra actors, making extra costumes, and feeding and housing these additional characters. 

There is that, too. Maybe if additional characters were kept more in the background, maybe that would save time, money, and effort. As long as it's too distracting, then I'd be fine with it.

@jasmine_tarkheena do you mean they'd be Featured Extras? However many days they're on set, they still need food, accommodation and costumes. 

@coracle 

True. I wonder if any of the stars from the Walden adaption were featured as cameos in Netflix's adaption. Or perhaps their families (like Sophie Cook's, who portrayed Susan in the BBC series, two children were made a cameo appearance in Walden's LWW).

@jasmine_tarkheena those are always nice little treats for long-standing audiences. 

I even just thought of, in The Magician's Nephew, what if they decided to give Jadis's sister a name. The final battle of Charn is all told as a backstory. They could have Jadis say her sister's name and show a little flashback.