'Physician, heal thyself,' goes an old proverb, and that applies with triple the intensity in Countdown. A young nurse (Elizabeth Lail) downloads an app that appears to be harmless, yet soon finds herself in a deadly race for her life when the app predicts she will die in three days. How can she save herself from a certain death?

Having already seen evidence of the predictive app's frightening power against others, and unable to delete it on her own mobile phone, the nurse becomes increasingly desperate. Perhaps a new device will eliminate the source of her anxiety? As our exclusive clip reveals, the young woman heads to a store, hoping to eliminate any possibility of contamination from the mysterious app, known as Countdown. Her prompt purchase, however, does nothing to assuage her fears, as she quickly realizes.

Watch the clip in its entirety below, then get tickets to see Countdown. The suspense-thriller will open in theaters everywhere on Friday, October 25.