Note: This review includes major spoilers for the 2017 film Happy Death Day.]

There’s a nagging irony pulsing at the heart of the 2017 horror-comedy sleeper hit Happy Death Day. In that film, Louisiana coed Theresa “Tree” Gelbman (Jessica Rothe) finds that she has been unaccountably damned to continually relive the day of her own murder – dying repeatedly at the hands of a mysterious, masked killer. Like Phil Connors in Harold Ramis’ now-beloved 1993 feature Groundhog Day, Tree eventually resolves to use her Sisyphean circumstances as an opportunity for self-improvement. The perspective gleaned from dying over and over allows Tree to evolve from a petulant, self-absorbed party girl to a halfway-decent person. Oddly, this moral growth proves to be almost incidental to the murder plot: Tree doesn’t so much solve her own slaying as eventually blunder into the realization that the killer is her secretly jealous and deranged sorority-house roommate Lori (Ruby Modine). It’s the sort of subtle narrative disconnect that can be attributed to ordinary sloppiness or intentional absurdity, depending on how generous one is feeling toward the screenplay.

What’s more, Happy Death Day never bothers to explain Tree’s slasher-film loop – like Phil’s Pennsylvania purgatory, it’s just something weird and inexplicable that happens – nor why evading death by preemptively shoving Lori out a window ultimately unsticks Tree in time. The film works largely due to the simplicity of its elevator-pitch conceit, the gallows fun director Christopher Landon and writer Scott Lobdell have with that premise, and especially Rothe’s star-worthy comedic turn. She elevates a relatively unpolished mean-girl-turned-final-girl role through sheer charisma and a delightfully committed, expressive performance. One could even go so far as to say that Rothe’s take is better (or at least more engaged) than Bill Murray’s in Groundhog Day, given that the latter actor never quite manages to shed his trademark above-it-all contemptuousness.

Ultimately, Happy Death Day is barely a horror film, masked-killer tropes and Blumhouse Productions logo notwithstanding. The feature is more of a PG-13 comedy-thriller with horror elements – a combination that is infinitely more interested in capitalizing on viewers’ familiarity with genre formulae than in scaring them outright. Moreover, unlike the characters in Wes Craven’s meta-slasher franchise Scream (1996-2011), HDD2U’s characters don’t seem to be aware of B-movie conventions. The only other film mentioned in the screenplay is Groundhog Day itself, referenced solely to set up a final, gratuitous punchline: Tree has never seen it. The dorm-room posters of nice-guy love interest Carter (Israel Broussard) do, however, hint at director Landon’s pop-cultural touchstones: Repo Man (1984), Back to the Future (1985), and They Live (1988).

It’s therefore not entirely unexpected that those films and other 1980s influences are at the forefront of Happy Death Day 2U, given that Landon serves as both director and screenwriter for the sequel. What is surprising is how definitively HDD2U tosses out any pretense that it is a slasher film. Aside from the presence of another killer – still clad in a creepy mask fashioned after the fictional Bayfield University’s mystifying mascot, the Baby – all the horror has been wrung out of the sequel. In lieu of chills, Landon serves up a giant, gooey homage to a very narrow mid-’80s wave of teen/college studio sci-fi comedies, including the aforementioned Back to the Future, My Science Project (1985), Real Genius (1985), and Weird Science (1985). (There’s a touch of Teen Wolf [1985] and Adventures in Babysitting [1987] in there, too.)

It’s certainly an unexpected turn for this nascent franchise, and a daring gear shift given the relatively light footprint of the preceding film. “Groundhog Day as a slasher film” was all the context one needed to appreciate what Landon and Co. were up to in the first outing. In comparison, Happy Death Day 2U feels like a fearless, sloppy, gloriously looney-toons swing for the fences, one that’s so committed to a specific retro stripe of harebrained campus farce that it often feels like a fever dream. Among the new characters introduced in this chapter is – honest to God – a buffoonish, sourpuss university dean. At one point, the heroes’ scheme depends on a character distracting said dean by pretending to be a sexy-yet-bumbling blind French foreign-exchange student. So … yeah: It’s broad as hell and utterly daft, but also sort of endearing if one can attune oneself to HDD2U’s odd quantum wavelength.

The obvious question is how the sequel undoes the seeming finality of the first film’s conclusion, in which Tree dispatched her would-be killer, reinvented herself as a less awful person, and got the proverbial guy in the form of the dorky-but-handsome decent dude Carter. HDD2U picks up literally the next day – Tuesday the 19th – after Carter’s dorm mate Ryan (Phi Vu) has once again spent the night in his car so that Tree can sleep over. He makes his way to the campus physics department, where he and his research partners, Samar (Suraj Sharm) and Dre (Sarah Yarkin), attempt to sort through some confounding data from their experimental “quantum reactor.” (The science in HDD2U is total gibberish, but in that breezy, non-bothersome way that echoes its 1980s forebears, as well as the mind-bending cartoon sci-fi of Rick & Morty – the film’s other major tonal touchstone.)

Abruptly, an irate Dean Bronson (Steve Zissis) appears with security in tow to confiscate the reactor, as the power-sucking device has been triggering repeated blackouts on campus. As if this crushing academic setback were not enough, Ryan is later ambushed in the deserted lab by a knife-wielding figure in a baby mask. As the blade plunges into his heart, Ryan jolts awake in his car: It is early Tuesday morning again, and he navigates the now-familiar events of the day with escalating bewilderment bordering on existential panic.

Fortunately, Tree is on hand to help Ryan navigate his temporal crisis. (Her ears perk up the moment he mentions his uncanny déjà vu, sending her into no-nonsense problem-solving mode.) She deftly summarizes the events of the first film in 30 seconds or so, then concludes that Ryan has become trapped in a similar loop. Together she and Carter – the only other person with whom she has discussed her Möbius-strip ordeal – accompany Ryan back to the physics lab in search of the waiting killer. Complications ensue, but to discuss anything of the plot beyond the 20-minute mark is to wade into major spoiler territory. Given that one of the crunchy pleasures of HDD2U is how it veers this way and that – the primary crisis switches three or four times over the course of the film – it’s best if viewers experience it for themselves.

However, the most conspicuous strength and weakness of HDD2U is apparent almost from the start. The sequel retroactively reveals a pseudo-scientific explanation for the events of the first film: Namely, Ryan and his partners’ quark-fiddling had the unintentional side effect of trapping a random nearby person (Tree) in a temporal loop. This conceit provides the entire justification for the sequel, which complicates the first film’s premise with familiar time-travel and parallel-universe snarls. Given how much kooky, often morbid fun Landon and his cast have with this elaboration, it’s hard to fault them for expanding the story in such a manner.

However, it’s also the case that HDD2U’s retconning unavoidably diminishes the self-contained quality of the first feature, not to mention undercutting its thrill- and character-centered approach. The commitment that Happy Death Day evinced in simply rolling with its Fortean weirdness focused the film gratifyingly, keeping the viewer’s attention on its Halloween-style theatrics and Rothe’s winning performance rather than nitpicky “Why?” and “How?” queries. Learning that It Was Mad Science All Along can’t help but feel like a bit of a letdown, particularly given that HDD2U’s loosey-goosey physics is more Back to the Future than Primer (2004). (Both hard-science geeks and clutter-hating cinephiles are bound to be unsatisfied on some level with the sequel’s approach.)

To its credit, Landon’s screenplay gets out in front of these inevitable criticisms. On learning that her ordeal was caused by a glitchy science project, Tree almost seems disillusioned, sulking that she had enjoyed thinking of her time loop as a gift from the cosmos, an opportunity to become a better person. Carter’s sensible riposte to this disenchantment – that Tree created positive meaning out of a meaningless quantum hiccup – points to the sequel’s low-key engagement with some surprisingly heady topics, such as the philosophy of personal identity. The introduction of temporal tangents and alternate realities into the series’ mythos allows Landon to replace the first film’s gauzy, Instagram-affirmation worldview with a tougher but more sure-footed “indifferent universe” materialism. This in turn permits HDD2U to deconstruct the notion of iterative improvement that undergirded the first film – and, indeed, almost every time-loop tale that has followed Richard A. Lupoff’s nihilistic 1973 short story “12:01 P.M.”

This is not to say that HDD2U is in any way a cerebral science-fiction film. Far from it: Landon’s sequel is almost gleefully dopey and cracked, mimicking the sensibilities of the broadest high-concept comedies of the 1980s. It’s the sort of the exercise that is so taste-dependent that it almost defies criticism. Whether an individual viewer will enjoy, for example, the sight of Tree diving into an industrial chipper-shredder while dressed as Evel Knievel – for absolutely no reason beyond the dumb, grisly spectacle of it – is not really subject to critical persuasion. It is the Hawaiian pizza of sci-fi comedy. (Although the gusto with which Rothe leaps into every one-off physical gag is undeniably admirable.)

What salvages HDD2U from its own cornball lunacy – and the film does, in fact, veer into cringy, clumsy schtick in a few scenes – is the surprisingly light touch that Landon exhibits in realizing the film’s overall retro atmosphere. In an era when so many filmmakers think of “homage” as an opportunity to scatter clunky allusions to other, better films, Landon takes a more lithe approach, replicating the tricky tone and less showy aesthetic attributes of its mid-’80s sci-fi-comedy antecedents. (Again, only one feature is actually name-dropped – Back to the Future II this time around – and only to elbow Tree for her pre-2000 pop-cultural illiteracy.) This isn’t the reverent look-and-feel replication of the Grindhouse (2007) shorts, but something closer to a 1985 feature made with contemporary film grammar and technology. The film’s nods to Reagan-era cinematic history don’t always work as smoothly as Landon imagines. Case in point: The filmmaker turns the final 30 minutes into a lo-fi heist that would be better suited to a campus sex comedy, a decision that proves lethal to HDD2U’s already-uneven momentum. In the end, it’s the little things that tend to leave deepest impression, such as the way that Bear McCreary’s score evokes but does not imitate Alan Silvestri’s indelible compositions for Back to the Future – until a quotation of the older film’s twinkling “time travel” cue makes a delightful late-game appearance.

Once again holding the whole thing together is Rothe, whose presence in insipid studio romances (Forever My Girl, 2018) and calculatingly “heartwarming” indies (Please Stand By, 2018) feels increasingly like a waste of a fearless comedic star. Which isn’t to say that the actress neglects the more heartfelt aspects of HDD2U. To the extent that the film has any ambitions beyond being a cheese-slathered junk-food feast, its effectiveness is attributable to Rothe’s ability to wring pathos out of daft situations – and to Landon’s unchecked confidence in her. In this respect, the film is arguably more successful than its predecessor. While Happy Death Day directed a good-natured finger-wag at late-Millennial/early-Gen Z selfishness, HDD2U is, remarkably enough, more reflective and melancholy. The film employs its outlandish sci-fi conceit to pivot from abstract ruminations to starker, more personal questions about identity and morality. And Rothe, to her endless credit, sells every tearful inch of the tough choices her character is obliged to make – when she’s not gamely tossing, flattening, shredding, poisoning, and electrocuting herself through a succession of slapstick deaths worthy of Wile E. Coyote.

Rating: B-