More from EW
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Thelma & Louise (1991)
Geena Davis and Susan Sarandon turned the macho-centric buddy movie on its head with a rebellious girl-power hit that no one saw coming.
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With True Lies and a Jack Ryan sequel also coming out that summer, who'da thunk the season's buzziest film would star a runaway bus, Keanu Reeves, and an unknown actress named Sandra Bullock?
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The Usual Suspects (1995)
Normally, we like to power down our brains in the summer, but Bryan Singer's pretzel-knot thriller turned guessing Keyser Söze's identity into a national parlor game.
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Heading into summer '95, Waterworld's colossal budget was topic No. 1. A few months later, all anyone could talk about was the lil' porker that grossed $64 million. ''That'll do, pig.''
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The Sixth Sense (1999)
The biggest shock about M. Night Shyamalan's ghost story wasn't its goose-bump ending. It was how a movie that freakin' great could fly under the radar until its August release.
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The Blair Witch Project (1999)
Some called it the scariest film ever; others said it was overrated. Either way, the $60,000 indie earned $141 million — and gave studio execs nightmares.
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Napoleon Dynamite (2004)
This nerdapalooza was the definition of a sleeper, with fans quoting lines like ''A liger... it's pretty much my favorite animal. It's like a lion and a tiger mixed?bred for its skills in magic.''
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March of the Penguins (2005)
If you ever doubt the greatness of this country, remember that in the summer of '05, a documentary about penguin mating rituals made $77 million — three times as much as Deuce Bigalow: European Gigolo. USA!
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The Hangover (2009)
Just when you thought you were over bromances, along came a bacchanalian bachelor romp that made Bradley Cooper a star — and paved the way for one of this summer's most anticipated sequels.