How suddenly is suddenly?
Between chapters?
Mid-chapter?
Between paragraphs?
Would you be doing it multiple times [switching back and forth]? Or just at one point?
I could see that it could/would get confusing for the reader if it wasn't absolutely clear when and why it happened...
I've seen the change in PoV used between a preface and the main story. It made it very clear that the preface was not part of the tale but the set-up for it... It gave the writer greater scope to introduce information that the character could not possibly know, but the reader needed to...
Can I ask... Why do you want to switch PoV?
That makes sense to me...its when the new chapter starts, its because the story reaches a point where it cannot be explained in first person POV ( or i simply cant do it) because the main character gets captured and tortured, and its where the villain is introduced.
i can put it up so you guys can read it if u want