There are actually a few works that come to mind where much of the twist is that the "main character" is not the main character of the story.
Perhaps one of the best examples is the Japanese film "The Hidden Fortress" which is an epic period piece about a war between feudal Japanese states... from the point of view of the comic relief. Naturally it played up many of the genre's staple characters as very sterotypical and the real pov characters having a comedic misunderstanding of the set. Hidden Fortress is, among film buffs, important as the dynamic of seeing major events in a drama was the basis for George Lucas making R2-D2 and C-3P0 the focus characters in his first Star Wars film... when we first meet them, they have as much clue as to why the Empire is shooting at them as the audience.
The "Buff the Vampire Slayer" had a similar episode titled "The Zeppo" (season 3) which is done in the style of the show's big season ending finales or major season plot game-changers... but from the point of view of the comic relief Xander, who is out of the loop and stumbles upon a much sillier evil plot that, if sucessful, could result in the big problem that Buffy is dealing with getting much worse. There are a few moments where the audience is given a staple element of the big episode, only for Xander's problems to be seen going on out of Buffy's out of context to the scene (one of my favorite moments is that Xander tries to inform Buffy about his problem, only to stumble in on Buffy her boyfriend Angel going through some dramatic agnst over the seriousness of danger both will be in fighting (it's to a parody level of the previous two seasons real drama between the two)... only to realize Xander is in the room and put a pause on the tense moment to address what he wants... but Xander almost realizes that it's one of those episodes and casually excuses himself with out mentioning the issue.
A more dramatic version can be seen in Star Trek: TNG episode "Lower Decks", the plot of which is a fairly tame episode of TNG but it's told from the point of view of a collection of Ensigns who have no idea what's going on, rather than the typical senior staff of the ship we follow. The locking out of the loop is played for drama as the ensigns are being assigned tasks that they realize paint a picture of some serious concern, but all but one have all the pieces to put together what's going on.