Every great accomplishment begins with a small idea, something that sparks the imagination or inspires a flurry of creative impulses, but sometimes small ideas stay small ideas. They may get gussied up in the trappings of larger ideas, but they remain small ideas. That appears to be what happened with Countdown, a high-concept horror flick that asks and answers the question, What if there was a mobile phone app that could predict the exact moment of my death? Elizabeth Lail stars as Quinn, a young nurse who, along with her colleagues, downloads the titular app out of morbid curiosity after an unusual encounter with a patient and discovers, much to her chagrin, that she may only have days before her time is up. And what happens to those who attempt to side-step their digitally predestined fate? It still comes to pass, of course, albeit under spookier circumstances. Critics say Countdown is a derivative thriller that reinterprets familiar ideas into a just-different-enough hodgepodge of jump scares and unnecessary subplots in order to stretch its central conceit to feature length. That said, most also agree that Lail and co-star Jordan Calloway are both likable leads, and it s a fairly short run to the finish line, so if you re just looking to get the heart rate up for a little bit, it may do the trick.