Klas Productions conducted a survey of their target audience, mainly 16-year-olds, to inform their thriller film. The survey found that psychological was the most popular thriller subgenre. As a result, they decided to change the subgenre of their film from crime to psychological. The survey also found that films with a female hero and set in an urban area were popular, so they decided to use a female hero and urban setting for their film. Popular films like The Girl with the Dragon Tattoo and Skyfall provided examples to draw from to appeal to their target audience.