[diebitter]

I think the opening shot of Indiana Jones and the Last Crusade, where you think you're looking at the back of Indy, but it's someone else, qualifies.

Also, there's a case that the first 20 minutes of Psycho is one long mislead of what the film is about is one.

Also, there's a number of Mario Bava films where you seem to witness something like a murder, but it unravels to be something else as the story proceeds.

And there's countless horror films where the scene is building to a scare which either happens sooner/later than you expect, or sometimes doesn't happen at all.