We round up 21 trailers from this summer's sci-fi movies

What movies are YOU looking forward to seeing this summer? To help you explore the possibilities, here's our list of 21 sci-fi summer movie trailers. From Jonah Hex to Piranha 3D, we've included every "summer" sci-fi, fantasy and spy flick we could dig up that either hasn't premiered or hasn't yet opened wide.

While most of the films are running wide (which means they'll be most everywhere), we also found some worthy-looking (and some questionable) entries that are opening in limited areas, too.

Cats & Dogs: The Revenge of Kitty Galore - Premieres July 30

The sequel to the funny original goes 3-D and focuses on Kitty Galore and her diabolical plan to make the world her own personal scratching post by taking down her canine enemies and her former kitty comrades from the cat spy organization MEOWS.

The film features the voices of Christina Applegate, Michael Clarke Duncan, Neil Patrick Harris, Sean Hayes and James Marsden.

Charlie St. Cloud - Premieres July 30

Charlie St. Cloud (Zac Efron) has a bright future ahead and is about to head off to college when tragedy strikes and little brother Sam dies. Trying to honor a promise he made to Sam, Charlie is torn between his past with what may be the ghost of Sam and his future with a newfound love.

The film Beastly was pushed to March 2011 to make way for Charlie St. Cloud, which originally was scheduled to open in October. The film stars Charlie Tahan, Amanda Crew, Kim Basinger and Ray Liotta.

Despicable Me - Premieres July 9

The supervillain Gru has an army of minions, and he's planning on the ultimate heist ... to steal the moon. And he plans to do it in "eye-popping 3-D." Gru delights in all things wicked and is armed with an arsenal of shrink rays, freeze rays and battle-ready vehicles to vanquish all who stand in his way. At least, that is, until he ends up caring for three little orphan girls named Margo, Edith and Agnes.

Featuring the voices of Steve Carell, Julie Andrews, Jason Segel, Russell Brand, Kristen Wiig and Will Arnett.

Inception - Premieres July 16

Leonardo DiCaprio and Ellen Page star in this mind-blower about a skilled thief who steals valuable secrets from deep within the subconscious during the dream state. However, on his last job he sets out to do the impossible, called inception—not to steal a secret, but rather to plan an idea.

Written and directed by The Dark Knight's Christopher Nolan.

Jonah Hex - Premieres June 18

Josh Brolin takes on the lead role from the gritty western comic book. Jonah Hex is a scarred bounty hunter of last resort whose past catches up with him when his latest bounty ends up being on his oldest enemy, Quentin Turnbull (John Malkovich), who has plans to unleash hell on earth.

Megan Fox stars as the prostitute Lila, who has a soft spot for Jonah.

The Last Airbender - Premieres July 2

M. Night Shyamalan takes on an epic 3-D adventure story about Air, Water, Earth, Fire—four nations tied by destiny when the Fire Nation launches a brutal war against the others. Aang, the last Avatar with the power to manipulate all four elements, teams with Katara, a Waterbender, and her brother Sokka to restore balance to their war-torn world.

Noah Ringer, Nicole Peltz and Jackson Rathbone star.

The Last Exorcism - Premieres Aug. 27

After 47 exorcisms, the Reverend Cotton Marcus (Patrick Fabian) is about to do his last one. His career has been spent helping the devout through prayer and trickery, so the Reverend decides to invite a film crew to document his final fraudulent days as an exorcist. However, this exorcism will test his faith as he's brought face to face with what might just be the devil himself.

Ashley Bell, Iris Bahr and Louis Herthum also star.

Nanny McPhee Returns - Premieres Aug. 20

Emma Thompson returns as Nanny McPhee, this time to help a young mother who's trying to run the family farm while her husband's away at war. When two cousins join her three kids at the farm, it's war, and only one thing will help ... Nanny McPhee.

Ralph Fiennes, Rhys Ifans, Maggie Gyllenhaal and Maggie Smith also star.

Ondine - Running now in limited release

Colin Farrell plays a fisherman named Syracuse who catches a beautiful and mysterious woman in his trawler's nets. Syracuse and his daughter, Annie (Alison Barry), begin to wonder whether the woman, Ondine (Alicja Bachleda), could possibly be a mermaid come to life.

Piranha 3D - Premieres Aug. 27

When an underwater tremor sets loose scores of big, prehistoric man-eating piranha, the 20,000 college kids enjoying Lake Victoria start looking like fish food. It's up to the local sheriff (Elisabeth Shue) and an unlikely group of strangers to band together to save the humans from the aquatic predators with those razor-sharp teeth and a serious attitude.

Directed by Alexandre Aja and starring Jerry O'Connell, Ving Rhames, Steve R. McQueen, Adam Scott, Jessica Szohr, Richard Dreyfuss and Christopher Lloyd.

Predators - Premieres July 9

The most dangerous killers on Earth have met their match when they find themselves hunted on an alien planet by a new breed of alien Predators. Splice's Adrien Brody stars as the group's reluctant leader.

The cast also includes Laurence Fishburne, Alice Braga, Louis Ozawa Changchien, Danny Trejo and Walton Goggins.

[REC] 2 - Premieres July 9

The sequel to the 2007 Spanish horror film co-directed by Jaume Balagueró and Paco Plaza. [REC] 2 picks up 15 minutes after the end of the first one as we go back to the quarantined apartment building, whose occupants have turned into mindless, violent beasts after being exposed to a virus. A heavily armed SWAT team and a mysterious government official go in to assess and neutralize the situation—and discover things have gotten far worse than they could possibly have imagined.

The American movie Quarantine was based on the original Spanish film. The film stars Manuela Velasco, Ferran Terraza, Ariel Casas, David Vert and Alejandro Casaseca.

Rosencrantz and Guildenstern Are Undead - Running now in limited release

A ladies' man, Julian (Jake Hoffman), gets his big break directing an off-Broadway version of Hamlet and casts his best friend and ex-girlfriend in the show. Unfortunately, he also discovers that this version of the play was adapted by a pale Romanian named Theo (John Ventimiglia) and he's in the middle of a 2,000-year-old conspiracy that involves Shakespeare, the Holy Grail and vampires.

The comedy was directed by Jordan Galland and stars Devon Aok, John Ventimiglia, Ralph Macchio and Jeremy Sisto.

Salt - Premieres July 23

Nope, there's not likely to be any sci-fi in this one, but we had to include Angelina Jolie's next big kick-ass spy flick, Salt. The story kicks off when a respected CIA agent, Evelyn Salt, is accused of being a Russian sleeper spy who is planning to kill the president. Salt goes on the run to clear her name and protect her husband.

Salt also stars Liev Schreiber and Andre Braugher.

Scott Pilgrim vs. the World - Premieres Aug. 13

When Scott Pilgrim (Michael Cera) develops a crush on Ramona (Mary Elizabeth Winstead), there's only one problem ... she has seven evil ex-boyfriends, and he has to defeat them all in order to get the girl. The film also stars Kieran Culkin, Chris Evans and Anna Kendrick.

The Sorcerer's Apprentice - Premieres July 14

Balthazar Blake (Nicolas Cage) is a master sorcerer in modern-day Manhattan trying to defend the city from his arch-nemesis, Maxim Horvath (Alfred Molina). He recruits some world-saving help in the form of a new, unwilling apprentice, Dave Stutler (Jay Baruchel), who gets a crash course in the art and science of magic.

From Jerry Bruckheimer and Jon Turteltaub.

Tales from Earthsea - Premieres Aug. 13

This Japanese anime film has been kicking around since 2006, but it's finally got a U.S. release date. Based loosely on the Ursula K. Le Guin Earthsea novel series, the story follows Prince Arren and his battle with his own powerful dark side.

Toy Story 3 - Premieres June 18

The gang is back for a new adventure in the latest sequel to the Pixar animated hit. When Andy goes off to college, his toys end up at a day care center where life is more than a little challenging for the new toys in town.

Tom Hanks, Tim Allen, Jodi Benson, John Ratzenberger, Joan Cusack, Don Rickles and Estelle Harris are back to voice your faves, with Michael Keaton popping in as the voice of Ken.

The Twilight Saga: Eclipse - Premieres June 30

Kristen Stewart, Robert Pattinson and Taylor Lautner return for another round of Twilight as Bella is once again caught in the middle of supernatural events, this time involving a string of vicious killings in Seattle and the ancient struggle between vampires and werewolves.

However, what's really important is Bella's decision between vampire Edward and werewolf Jacob.

Valhalla Rising - Running now in limited release

In 1000 A.D., a mute warrior with supernatural strength is held as a slave until a young boy helps him escape. They join a band of dispossessed Vikings as the warrior journeys to uncover the mystery behind his own origins through dangerous lands and against terrifying enemies.

Mads Mikkelsen and Maarten Stevenson star in this film from Nicolas Winding Refn.

The Wild Hunt - Premieres July 16

This twisty Candian thriller explores what happens when a medieval re-enactment game goes too far after a nonplayer crashes the event to win back his girlfriend. The independent film was made on a shoestring budget by writer/director Alexandre Franchi and stars Kaniehtiio Horn, Ricky Mabe, Kyle Gatehouse and Trevor Hayes.

So—which movies do you want to see?

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