The trailer for Countdown introduces a new kind of horror monster for the digital age - an app that can predict exactly when people are going to die. Written and directed by Justin Dec (making his non-TV feature debut), the film stars Elizabeth Lail as Quinn, a young nurse who downloads said app, only to discover that she has just three days left to live.

Lail signed on for Countdown in March, following her breakout performance in the psychological thriller TV series You (which premiered on Lifetime last year before becoming a massive hit by streaming through Netflix). She's joined by a cast that includes Black Lightning's Jordan Calloway and Supergirl veteran Peter Facinelli, in addition to Talitha Bateman, Tichina Arnold, and P.J. Byrne. Production on Countdown clearly didn't take very long, as the horror-thriller is already scheduled to arrive at the end of October.

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STX released the full-length trailer for Countdown online this morning, and just in time for it to screen with the studio's latest film, Hustlers, in theaters starting this weekend. The promo covers the broader strokes of the movie's plot, which is a bit reminiscent of the premise for The Ring (only updated for the post-VHS era). Quinn, of course, doesn't take the app seriously until creepy things start happening to her, and she begins talking to people who learned the hard way just how accurate the app's predictions really are. Check out the trailer, below.

Countdown isn't the only movie opening this fall about the dark side of apps and smartphone technology either, with next month's comedy Jexi revolving around an A.I. lifecoach that could perhaps best be described as an evil Siri. Based on the trailer, it looks like the app in Countdown involves some kind of curse that Byrne's character (a priest, judging by his attire) believes they can break by simply defying its prediction for as little as one second.

In addition to The Ring, Coundown bears a resemblance to last year's Blumhouse offering Truth or Dare, which revolved around a group of college students who inadvertently activate a curse by playing the titular game. The trailer makes it look like a fairly silly run of the mill slasher film, though it also suggests the movie is well-aware of the inherent goofiness of its setup. So far, the Countdown footage seems to have a PG-13 vibe to it, which means it will be targeting teenagers in the mood for a scare around the Halloween season when it launches next month. Who knows, the (literally) killer app might yet get a franchise of its own.

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Countdown opens in U.S. theaters on Friday, October 25.

Source: STX