Yup, this is a thing now. Nathan DeLuca and Eve Beauregard are the cosplayers at the heart of this BioShock Infinite tribute, falling through the sky in the name of fancy dress.
Sure, the background is from the game's promotional art, but if you're expecting cosplayers to be able to construct a floating metropolis they can jump off just to take a photo, you're... weird.
To get the effect, they had to use two photographers, since Eve is in Australia. So Booker is actually jumping, while Elizabeth's fall "involved an elaborate set up with a fan, a chair, fishing line and lighting stands".
BioShock Infinite Cosplay [Facebook]