'Countdown' will make you want to toss your phone

This anxiety-inducing horror movie likely just escaped an R rating from the MPAA. Though there's little gore, “Countdown” is genuinely gnarly at times, featuring moments of pure terror - and one of the most satisfying single uses of the F-word in recent cinematic memory.

After the mysterious passing of a patient, nurse Quinn (“You” charmer Elizabeth Lail) downloads the even more mysterious app he blamed for his death, named Countdown.

It predicted his demise down to the second, and she and the hospital staff get it from the app store out of a morbid curiosity.

Of course, they accept the user agreement without reading, which turns out to be a literal devil's bargain, making Facebook look good.

While her coworkers are given decades to live, the program tells Quinn she has just days remaining.

She desperately tries to escape her fate as the minutes tick by, and she's joined by another user, Matt (Jordan Calloway), whose death is also imminent.

Despite the plot holes and internal inconsistencies, “Countdown” does have a little more on its mind than just making its audience gasp and giggle in terror.

Quinn's interactions with a slimy doctor (a well-cast Peter Facinelli) allow for a pointed commentary on sexual harassment, but using the opioid crisis as a plot device proves less strong.

This is a fun movie at its fast-beating heart, and reminding viewers of thousands of deaths feels out of sync with its enjoyably silly and creepy tone.

But for a film called “Countdown,” it's surprisingly bad at timing. Final minutes of characters' lives stretch like a teen's gum, when using a clock in real time would've worked far better to keep the tension.

But writer-director Justin Dec is otherwise effective at bringing the scares. Though it features loving nods to “Freaks” and “The Shining,” “Countdown”‘s source code feels more like a hybrid of “Final Destination,” “Unfriended” and “The Conjuring.”

This isn't a subtle, moody film filled with a sense of unease; instead, jump scares are around every corner. If that's all you want from a horror movie, you'll have a very good time - and an elevated heart rate for its speedy 90 minutes.