Leia and Chewy walking down the street

Photo: Sandy Huffaker/Getty Images

Princess Leia and Chewbacca walk hand in hand down 5th Avenue on July 19 during San Diego's annual Comic-Con.

Over the course of four days, the San Diego Convention Center is booked up with celebrity panels, artist workshops, movie premieres, trade markets, autograph booths and, of course, the thousands of cosplayers who go to the extreme to perfect their costumes.

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Zombie at Comic Con

Photo: Sandy Huffaker/Getty Images

Lisa Kruis, decked out in a zombie outfit, stares hungrily into the camera.

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Venture Bros girls at Comic Con

Photo: Sandy Huffaker/Getty Images

Women dressed as characters from the Venture Bros pose for a photographer inside a picture frame.

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Steampunk pirate band at Comic Con

Photo: Fidencio Garrido/Flickr

A band of pirates play a tune for passersby outside the convention center.

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Super dog at Comic Con

Photo: Sandy Huffaker/Getty Images

Beckham the dog sports a Superman pet costume while on a walk outside the convention center.

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Zombies at Comic Con

Photo: Fidencio Garrido/Flickr

A con attendee is taken captive by a pair of hungry zombies.

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Storm troopers at Comic Con

Photo: Fidencio Garrido/Flickr

Stormtroopers march through the streets of San Diego.

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Catie Leary is a photo editor at Mother Nature Network. Follow her on Twitter and Google+.