Question: My novel begins with a prologue that depicts an action sequence involving the three main characters (2 protagonists, 1 antagonist). The sequence takes place near the end of the story, which consists of two parts: the first part being when the protagonists are 10 years old, the second when they are 16. How do I integrate the prologue? Do I insert it as a chapter, verbatim, in the appropriate spot of the storyline? The prologue is originally through the eyes of one of the protagonist, third person omniscient...is it acceptable to switch the POV to the other protagonist for that actual chapter instead, or is that too disruptive to the reader?
Deanna, you have given me quite a brain-twister here (unintentionally, I'm sure). Your question is so full of contradictions I was tempted to simply not attempt an answer. But then I thought that if I can unravel this knot a little, maybe that might help you clarify your own thoughts.
It could be just that if we get clear about some terms, the answer will appear.
Here's what I mean by contradictions...
1. The "prologue is originally through the eyes of one of the protagonist, third person omniscient."
You can either tell the story through the eyes of one character or from an omniscient point-of-view, but not both. Omniscient means "all-knowing," and it's the mode that offers a bird's eye or godlike perspective on the story--one that can move around from place to place, character to character.
Third person, limited, narration is confined to the main character's perspective. The reader only knows the main character's thoughts and feelings and what he/she perceives of the external events.
2. This is a prologue, but "it takes place near the end of the story." Generally, prologues describe events that take place before the story properly begins. (The word "prologue" literally means "before the story.")
Perhaps you are not telling the story in chronological order? If so, and you want to begin with an event that takes place near the end of the timeline, then perhaps it's more of a "flash-forward"?
3. The prologue features two protagonists. This is a minor note. I think you simply mean two characters who play major roles and are not on the side of the villain. Generally, there is only one protagonist--the character who is leading the pursuit of the story goal. Other characters may contribute in different ways, of course. But it would be a little redundant to have two archetypal protagonists, especially within the same scene, because they would do nothing but mirror
Now, I'll try to answer your questions..."The prologue is originally through the eyes of one of the protagonist, third person omniscient...is it acceptable to switch the POV to the other protagonist for that actual chapter instead, or is that too disruptive to the reader?"
The rule is that you should not switch points of view within a scene, because that is jarring for the reader. Readers like to imagine themselves in the shoes of the POV character, and a sudden switch destroys that illusion, much like an actor who breaks character. Generally, it is best to only switch points of view at chapter breaks.
That said, it is possible to present a scene twice, from two different points of view. You might do this if the second telling reveals important things which the first POV character did not perceive (due to age, perspective, awareness, etc.) in order to let the reader and the characters reevaluate the event.How do I integrate the prologue? Do I insert it as a chapter, verbatim, in the appropriate spot of the storyline?"
You have the choice of presenting events in chronological order, or telling the story out of sequence.
For instance, if the inciting incident or the initial events of the overall story do not involve the main character, they can be told in a prologue so that the first chapter begins at the point where the main character enters the story.
In other stories, it makes more sense to begin with the main character and use a flashback at some point to fill the reader in on what happened.
In non-chronological stories, you might begin at the ending, putting a flash forward in place of the prologue. You might do this to create a mystery, where the reader wonders what could have happened to create the situation in the flash forward. The rest of the story answers that question.
You can also choose to insert the flash forward at another point along the timeline. Generally, it is better to put it into its own chapter and give it a very different tone than the rest of the story. Give the reader some clues or cues to make it obvious that this event is a departure from the timeline. If it's not too long, you might even consider putting this chapter in italics.
You have to trust your feelings when choosing the right place to insert this event.
If I've misinterpreted your question or you have a follow-up, please feel free to post it as a comment below and I'll try again.