Every year has its share of no-brainer box-office hits. In 2013, it came as a surprise to absolutely no one that franchise flicks like "The Hunger Games: Catching Fire" and "Iron Man 3," animated sequels like "Despicable Me 2" and "Monsters University" and even a troubled zombie movie starring Brad Pitt were going to put a lot of butts in the seats and rake in the cash.
However, every year is not without its box office surprises, too; those films that defy expectations because you just never quite know what American audiences are going to respond to from one weekend to the next. Here are 10 2013 releases that made a lot more money than anyone was expecting.
[Related: The 25 Best Movies of 2013]
1. "Gravity": $252 million
Box-Office Prediction: $85 million
Back in August, BoxOffice.com predicted that Alfonso Cuarón's groundbreaking sci-fi thriller would make a mere $85 million. Cut to its early October release date and "Gravity" pulled in audiences with strong festival buzz and "You gotta see this!" word-of-mouth. It looks to be a shining star during awards season as well, with four Golden Globe nominations, a SAG nom for Bullock and a Movie of the Year nod from AFI so far.
2. "The Croods": $187 million
Box-Office Prediction: $150 million
We're surprised that an animated film about a wacky clan of cavemen was predicted to earn as high as $150 million, but "The Croods" surpassed even that generous forecast. It's certainly the biggest hit that Nicolas Cage has had in a while, and "Turbo" star Ryan Reynolds can say he had at least one voice gig that did well in 2013.
3. "The Heat": $159 million
Box-Office Prediction: $152 million
Here's another one that had a pretty high forecast to begin with ... and still managed to throw a little more on top. Never, ever doubt the power of the raunchy R-rated comedy, especially when Melissa McCarthy is around — her grrrl power with Sandra Bullock in director Paul Feig's send-up of the male-dominated buddy cop genre already has a sequel in the works, which at this point is more likely to actually happen than "Bridesmaids 2."
[Related: The 10 Worst Movies of 2013]
4. "We're the Millers": $150 million
Box-Office Prediction: $82 million
What was that we were just saying about the power of raunchy R-rated comedies? "We're the Millers" was the biggest surprise of the dog days of August, completely blowing expectations out of the water (and straight to the Mexican border) as Jennifer Aniston showed you can still do a striptease at age 44 and Jason Sudeikis proved that he's more than just the guy who's dating Olivia Wilde. What's strange is no one seemed to actually, you know, love the movie — they were just strangely drawn to it, which conjures all sorts of conspiracy theories.
Speaking of 'conjures' ...
5. "The Conjuring": $137 million
Box-Office Prediction: $64 million
Between this and the $83 million box-office take of "Insidious Chapter 2," we're surprised that every Hollywood studio hasn't canceled all of their scheduled tentpoles in favor of simply producting low-budget horror films ... with all of them directed by James Wan. What's even more remarkable about the box-office tally of "The Conjuring" is accounting for its R rating and the fact that it was released right smack dab in the middle of the summer — not exactly the Season of the Witch, traditionally, mind you.
6. "Identity Thief": $137 million
Box-Office Prediction: $62 million
Oh right, before "The Heat," Melissa McCarthy had another box-office hit in 2013, one that doubled the box-office prediction of $62 million, courtesy of BoxOffice.com. Her partner in moolah-making in this one was Jason Bateman, who's becoming quite the formidable big-screen force in his own right thanks to the success of ensemble pieces like "Horrible Bosses" (2011) and two-handers like "The Change-Up" (2011). "Identity Thief" also managed to score that impressive take as a February release, and everyone knows that's a month usually reserved for movies no one wants to see (and which usually remain unseen).
[Related: The Top 13 Performers of 2013]
7. "Now You See Me": $117 million
Box-Office Prediction: $50 million
No one who saw it really remembers it, but obviously a lot of people at least bought a ticket as this so-so thriller about a bunch of Robin Hood-ish stage illusionists managed to pull off quite the box office magic trick. Audiences may have been drawn by that equally baffling ensemble cast, including Jesse Eisenberg, Woody Harrelson, Morgan Freeman, Mark Ruffalo, Isla Fisher, Mélanie Laurent, and Isla Fisher.
8. "Lee Daniels' The Butler": $116 million
Box-Office Prediction: $78 million
Pretty much everyone expected the film formerly known as simply "The Butler" was going to be something of a sleeper hit, but director Lee Daniels's ensemble political/historical drama managed to keep the interest of American moviegoers a bit longer than anyone anticipated, claiming the No. 1 spot at the box office for three consecutive weeks. Equally surprising is the complete lack of Golden Globe nominations.
9. "Olympus Has Fallen": $98 million
Box-Office Prediction: $48 million
OK ... so maybe there is life for Gerard Butler post-"300" (2007)? This year's White House invasion movie that doesn't star Channing Tatum doubled its box office expectations as a March release with a heaping helping of ultra violence that earned it an R rating. It probably didn't make anyone's list of all-time favorite movies, but "Olympus Has Fallen" arguably benefited from being released a month after the astonishingly disappointing "A Good Day to Die Hard" — in fact, one could argue that "Olympus" was what the fifth "Die Hard" movie should've been.
10. "Instructions Not Included": $44 million
Box-Office Prediction: N/A
Where the heck did "Instructions Not Included" come from? This Mexican import was quietly released during the very last weekend of the summer and completely won over audiences with its tale of a former rollicking bachelor, the baby girl left on his doorstep and the birth mother who unexpectedly shows up six years later to tear their happy lives asunder. Never underestimate the power of father-daughter relationship movies, no matter what language it's in.