@vinceguerra I'd love to see something like that too — my own headcanon is also that Peter, while studying with the Professor during the events of VDT, started talking with him further about Narnia, and that's where Digory confirmed that he had been to Narnia as well. Then some time after that, he invited the Pevensies and Eustace and Jill to meet somewhere with him and his old friend Miss Plummer ("but you can call me Aunt Polly!", as I'm sure she very soon told them), and that's how the Friends of Narnia began. If I were making a film or TV adaptation of all seven Chronicles, I'd definitely include these things "in between" the main stories, to tie all the action together.

However, when it comes to the movie that's currently being made (which we think is The Magician's Nephew, but even that hasn't been officially confirmed so far), there are hints and rumours swirling around that suggest it'll be very different from all the previous screen adaptations of Narnia, and it's unclear how much resemblance it'll bear to the actual books. It at least looks likely that they won't try to establish any kind of continuity between the previous franchise and this one. (And even if they did, William Moseley and Jim Broadbent are now nearly 20 years older than they were when they last appeared in a Narnia film, so it just wouldn't work — Peter in particular needs to be believably in his mid-to-late teens for this scene, not in his mid-to-late 30s.)

I wish we could have a Narnia film series that stuck closely to the books while filling in things like this that are implied but not shown directly in the stories. But at the moment, that doesn't seem to be something we can be too confident about. 

@courtenay It could always be later in Peters progression. He could really be any age and twenty something actors play teenagers all the time (Cobra Kai) but that's just a thought. 

I like filling in the Friends of Narnia meeting. 

@vinceguerra I like the idea of seeing the Friends of Narnia meeting. I've got a few ideas how this could be used in movies too. 

But I'm afraid Peter in his late teens, preparing for a university entrance exam could not be played by Will Moseley at  almost 40.

Honestly, I think one of the best things about The Magician's Nephew is that it is a fairly small and intimate story - the stakes are largely internal and mostly personal for Digory (compared to most of the other books where the stakes are usually external - i.e. saving Narnia from some outside threat)

Therefore I think I would generally like to keep.the purity of that opening moment in tact - either a close up on Digory crying, or starting with Polly overhearing someone crying. It really sells the entire personal journey of both characters in just one moment.

I also think that most of the Narnia books follow a fairly simple formula:

• The children are somewhere boring and mundane (stuck in a dusty old house, at a train station waiting to go back to school, in the spare bedroom of their aunt's)
• The children get whisked away to a fantasy land at a time of great sadness (eternal winter, civil war, missing heirs, dying Caspian)
• The children return joy and wonder to that place.

Even MN follows that same basic pattern - Uncle Andrew's House -> Charn -> Narnia.

Therefore, whilst I can see that there is often the temptation to jazz up the intros and make them more exciting, it's usually actually to the betterment of the stories if the intros are as dull, depressing, and mundane as possible 

My hunch is it will start in darkness somehow. Like an 'In the beginning there was nothing' vibe, to anticipate the creation of Narnia later in the movie. With perhaps just an indistinct close up of lion paws treading the ground to whet the appetite of the audience, before transitioning to London.