Stop me if you've heard this before, possibly in the exact same way you heard it yesterday: Happy Death Day, opening Friday, is a riff on Groundhog Day, the classic Bill Murray comedy about an arrogant weather man who lives Feb. 2 over and over until he gets it right.

It may sound familiar even if you're not stuck in your own time loop because this year saw the release of Before I Fall, in which a teenage girl (Zoey Deutch) keeps reliving a day that ends in a tragic car crash; the Netflix debut of Naked, in which a feckless man (Marlon Wayans) keeps waking up naked in an elevator on the morning of his wedding; and the Broadway birth of Groundhog Day, the musical, in which, well, you know. Happy Death Day is the slasher-movie version: A disdainful sorority girl (Jessica Rothe) keeps getting stabbed to death by a masked attacker on her birthday, resetting with every death. She uses this time-loop as an opportunity to track down her killer.

From a creative standpoint, it's easy to see why this structure has been repeated: The conceptual heavy-lifting has already been done by another movie, but there's still room for individual invention. Of course, Groundhog Day didn't invent the idea of getting stuck in a time-loop, but it's the clear reference point for most of the time-loop movies that have followed — especially in its conceit that reliving the same day over and over should become a vehicle for self-improvement. That's true of the best Groundhog Day successor Edge of Tomorrow, where Tom Cruise gradually sheds his glib cowardice and becomes a super-soldier as he re-lives a battle with marauding aliens.

Before I Fall and Happy Death Day are notable for refocusing this self-improvement plan on young women. (The most negligible entry of the year, Netflix's Naked, has both the clumsiest employment of the gimmick and the flimsiest thematic backbone; it's about a guy who needs to, like, try a little harder.) Fall's heroine is a popular girl complicit in her friends' bullying behavior, while Happy Death Day's Tree is, if not the meanest girl in her sorority, perhaps abdicating the title due to lack of effort. She brushes off her roommate, rolls her eyes at a guy who helped her out after a night of heavy drinking, and ignores phone calls from her dad.

In a normal slasher picture, Tree would be maybe the second or third victim — the bitchy friend or frenemy whose death brings ghoulish satisfaction. One of the most fun aspects of Happy Death Day (and it is a lot of fun) is the way it toys with genre conventions, turning a knife-fodder caricature into a winning Final Girl with emotional depth. It also plays around with slasher movie routines; most of its different "kills" are variations on the same timeline.

But as with Before I Fall, the engine of the story is how this girl can learn to be a better person if she's just forced to live the same day over and over — treating the supporting characters and extras in her life, introduced in that first 15-minute run-through of the day, with more empathy or respect. Before I Fall turns this effort into belabored melodrama, but at least it's a self-improvement directive written and directed by women; there's something faintly condescending about the men who wrote and directed Happy Death Day putting Tree in her place, implying that her list of murder suspects is relatively long because of how she treats people (murder hardly seems like the right comeuppance for withering eyerolls). But the movie rights itself through a late sequence that makes Tree's application of her life lessons — her attempts at kindness — seem both utterly half-assed and charmingly energetic.

Happy Death Day also features the best 2017 wrinkle to the time-loop formula: Tree starts sustaining some injuries from one day to the next. She wakes up looking the same, but grows weaker and accumulates scar tissue — the process takes a toll on her. It's a physicalization of the psychological torture usually associated with getting stuck on a repeating day. Getting the day right is hard work.

Time-loop movies convert that hard work into sharply edited gag reels; like Groundhog Day and Edge of Tomorrow, Happy Death Day launches into a funny trial-and-error montage once its heroine thinks she understands the game at hand. (This is something lacking from Before I Fall, which treats its repeated days more methodically, in keeping with its more serious — borderline leaden — tone.) Though time-loops involve a surrender of control, these newer versions are fantasies of focus, inviting us to imagine a world where one specific task demands our attention. This is the biggest departure from Groundhog Day, where Murray's character must arrive at his own conclusions about what to do with his looped time (the catastrophe he's preventing is just his everyday life). Before I Fall, Happy Death Day, and even the wan Naked have problems that must be addressed, and going off on side adventures, attractive as the prospect may be, won't solve anything.

This may be the current appeal of the time-loop structure: In a world where bad news cascades through our various screens and seems to compound every week, there's something comforting (to the audience, if not the character) about the notion of not moving forward until this one damn problem gets definitively solved. The young women of Before I Fall and Happy Death Day have social media, real-life friends, and plenty of privilege, but none of it can help them. Instead, they have infinite chances and no shortcuts. Of course, a 100-minute movie is a shortcut, too — capable of transforming work into something like escapism.