It begins as a harmless parapsychological experiment. Three researchers from a university set out to prove a scientific theory correct: "Ghosts only exist because we believe in them." They attempt to create a spirit using their minds, and if it succeeds, they'll be able to prove that supernatural events can occur as long as there are people believing in them. To their excitement--and eventual horror--they pull it off and the apparition is born.

The entity starts to haunt a young couple, Kelly (Ashley) and Ben (Sebastian Stan), and their only hope is the expertise of paranormal professional Patrick, played by Tom Felton. He explains that the being feeds on their fear, saying, "Once you believe it's real, you die."

When MTV News caught up with Ashley last month, she told us that the thriller--hitting theaters August 24--keeps audiences guessing. "There is amazing CGI work in the film. I don't want to give too much away, but I will say the visuals are very compelling," she said. "The fear is built through suspense and fear of the unknown, rather than the blood or gore of a horror film."

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What do you think of the trailer for "The Apparition"? Will you see the summer flick when it hits theaters? Tell us in the comments and on Twitter!