What’s a movie that has an exceptional first and second act, only for the third to wrap it up perfectly making it an amazing viewing experience?

I know the title is a mouthful, but a great example of what i mean is Whiplash

The first two acts are gripping and keep you guessing until the movie basically “ends” when it cuts to black at the penultimate moment. But then, we get that magical third act that not only heightens everything before it, but extremely satisfyingly wraps up the entire narrative.

Another great example of what i just described is Top Gun: Maverick, which does practically the same thing. Gripping and brisk first two acts, and suddenly a third act that makes everything that much better.

So with these movies as an example in mind, what’s a movie that has an exceptional first and second act, only for the third to wrap it up perfectly making it an amazing viewing experience?

Edit: Thanks for the replies! I have seen Mulholland Drive, Fight Club, BTTF, The Prestige, and all of the Cornetto Trilogy (Shaun, Hot Fuzz, Worlds End) and agree that these are welcome inclusions.