Dear Jerusha: Can you have an opening chapter in the point-of-view of someone who isn't the MC? [Emma notes: that's main character, not master of ceremonies] I'll try to explain. My opening chapter is in the point-of-view of a doctor. Her patient, James, is a main character, but is unconscious after an overdose of illegal drugs, and the scene is with James's family, in the hospital. The whole scene is from the doctor's point-of-view, but one of the family there, Edward, is also a main character. The reason I did it this way is because I needed a negative view of James, before the novel gets into why he is how he is. But a couple of my writers' group have said that it could be confusing or wrong-footing to have a chapter, especially the first chapter, in the point-of-view of a character who isn't important all through the novel (though she does appear again). And someone else has said that I definitely shouldn't do this, because it's important that the reader empathises with the MC, and to show the MC in a negative light makes that harder.
Writers' Groups, eh? Who needs 'em? [Emma notes: me] I really like the sound of this, if it's handled right; it introduces us to an important group of people, and expresses the dynamics of them, at a really crucial point, all in one. A first chapter - among many other things - is teaching the reader how to read this novel, but if the book uses several points of view, perhaps in separate chapters, then I would argue that there's no reason you can't use the doctor's here. In a narrative in third person there is, by definition, a privileged narrator who can admit the reader to any mind or point of view it chooses. There's also a long history of using a point-of-view character to tell someone else's story: Wuthering Heights, for example, and to some extent The Great Gatsby. And the really cracking story which won Second Prize in the Frome Festival Short Story Comp, "Mr Plumb" by Stanley Walinets, did exactly that. It was very successful, and it made me realise that it's a rather under-used technique. (You can read it and most of the others here, by the way. Highly recommended.)
What I would say is that you'd need to be careful not to get us too involved in the doctor's own life and mind, because (as I was discussing the other day here), readers will take that as a signal to invest in her. They will then be disconcerted - even frustrated - that she turns out not to be important. But to use her largely as a pair of eyes and a voice, looking at and evoking various characters who we are going to be investing in, could be great. She's not a neutral, external narrator in the classical sense, as the entity we call "Hemingway" is in the stories by that writer who married Martha Gelhorn and eventually shot himself; she's internal, not external to the scene, and her personality will affect what she sees and tells us about in the scene. But she is rather like an external narrator, external to the family and their situation, and to that extent she's a good camera to use in introducting them, their situation and dynamics.
"Empathising" means "feeling with", in the proper sense: we can empathise with morally bad feelings (see American Pyscho), as well as morally good ones whether they're pleasant or unpleasant We're not likely to feel deep empathy with the doctor - that would be counterproductive, indeed, since you don't want us to invest in her emotionally. But it can work really well to get a negative view first of someone - in this case James - who later turns out to be important for us. Shakespeare does it to Othello; the first things we hear about him are entirely negative, and at that stage we've no reason to disbelieve them. To hear first negative things about James, to have been made to lead ourselves up the garden path a little, and then find our easy assumptions confounded, makes him a much more rounded person. And we're therefore more likely to empathise with him, for sharing our own mix of good, bad, positive and negative, than if he was two-dimensional. Romance writers do it all the time, too - the apparent baddy who turns out to be the Great Love - and so do Thriller writers, with the admired boss who turns out to be framing the MC. Obviously, the negatives and the positives need to be consistent with each other: James's vices and virtues need to fit together, but that's true of any character with any complexity... which is surely all characters with a bigger than walk-on part in your novel.
The last usefulness of a narrative technique like this, well-handled, is that it can build up narrative tension to have a conversation which circles around a so far absent character. There are lots of plays which work like this, with much of the first scene or even act built from the characters discussing Uncle Whoever, who's on his way, and everything to do with the estate having to be sold, and what will he think, and then right at the end of the first act - ta-da - Uncle Whoever arrives. Curtain. And we spend the interval longing to get back in and find out what will happen. And of course there's the ultimate, meta-dramatic, Waiting for Godot option, where he never appears at all. But that's a different story.