One thing that Love and Monsters cannot be accused of is a superfluity of original ideas. The film, written by Brian Duffield (of the bald-faced Alien knock-off Underwater) and Matthew Robinson (of the bald-faced everything knock-off Monster Trucks), is something of a grab bag of sci-fi and post-apocalypse narratives of every sort, especially where those three categories overlap. Most transparently, it is one of the most unabashed clones of Zombieland you could ever hope to see, from its hapless nebbish of a hero who chattily discusses the whole thing in voice-over to its tough cowboy-like male mentor/asshole antihero figure. But the list of films, television, and video games that appear to have fed this or that idea, scene, plot point, or design element would be extremely long and include both massive popular hits and near-forgotten cult curios.

This is, unexpectedly, a strength. Part of the the benefit to any film that steals from basically everything is that it no longer registers that it's stealing from any one thing in particular, and in the end, the combination of all these disparate ideas ends up feeling brand new - every single ingredient might be familiar, but all of them in this mixture ends up feeling sort of exciting and fresh, in its weirdly stale way. This is certainly the case for Love and Monsters, which spends a substantial portion of its 109-minue running time as quite a punchy, playful sarcastic comedy on post-apocalyptic themes. Indeed, if it didn't run at full speed into one hell of a bad final act, I'd be ready to declare this one of the best genre films to have straggled its way out of the muck of 2020. At the very least, it's one of the better post-apocalypses in recent years, presenting a familiar sort of ruined world with great gusto and comic breeziness.

It is, to begin with, seven years after things went to hell: an asteroid was on a collision course to Earth, and the collected nations of the planet agreed to set aside all our differences to blow it to hell using an ungodly number of rocket-powered missiles. The good news is, the asteroid was obliterated. The bad news is, all those rockets blanketed the planet in a cloud of chemicals that mutated every cold-blooded animal on the planet - reptiles, amphibians, insects, fish - mostly by making them very large, mostly indestructible, and hungry for human flesh. This doesn't hold up to basically any scrutiny on a number of counts, but the good news is that the film gets it all out of the way quickly and with terrific upbeat, prattling energy, putting it in the mouth of Joel Dawson (Dylan O'Brien), a nerdy 16-year-old at the time of the collapse of the world, and a nerdy young adult now. Joel is part of the small clutch of humankind that survived the chemicals, the monsters, and the great war that led to the destruction of most of the mutants and nearly all of the people, and presently live in underground bunkers scattered across the globe, separated by miles of deadly landscape.

As we see in a flashback, the terror began right when Joel was about to have fumbling teenage car sex with his girlfriend Aimee (Jessica Henwick), presumably for the first time; he is now the only inhabitant of his bunker who isn't partnered up. But he's also discovered that Aimee is still alive, some 85 miles away, and despite being conspicuously bad at all of the necessary tasks of survival - he cooks for the rest of the bunker, and freezes up like a terrified rabbit when he's called upon to do anything else at all - he decides to fight was way through the wilderness to find her distant bunker, and declare his love, still sharp all these many years later.

It's both exactly as corny as it sounds, and also much less: the film doesn't ever agree with Joel's conviction that he and Aimee were soulmates, necessarily. Mostly, it treats this less a story of love per se, notwithstanding the title, than of a story about hope: the need for there to be something to fight for, something worth all the work it takes to survive in a hostile world. O'Brien's surprisingly nuanced performance, considerably more interesting than anything I've ever seen him do (which is mostly The Maze Runner and its drab sequels, so not a tough bar to clear), supports this: while he plays Joel as certainly lonely and probably really very sincere in his belief that he and Aimee had something special, he plays the character far more as someone who's mostly just tired of recognising his own helplessness and ineptitude. The film's best character moments aren't the ones foregrounding the love story, but the ones where Joel encounters a pair of survivalists out in the wilds, gruff old man Clyde (Michael Rooker) and tough-skinned little girl Minnow (Ariana Greenblatt), who encourage him in his self-confidence, or his relationship with the stray dog Boy, played impeccably well by a pair of dogs named Hero and Dodge; the "boy and his dog" format is a mainstay of the genre dating at least as far back as, well, A Boy and His Dog, from 1975, but it's given a particularly fine workout by Love and Monsters. The relationship between Joel and Boy is an excellent version of the routine whereby a character tells us about himself by talking to a nonspeaking companion, in addition to providing a handy way to chart how much Joel is changing from a victim to a protector.

This is all very fine and good so far as it goes, and director Michael Matthews carries it off with an effective amount of absurd humor that showcases O'Brien's talents well, while providing some tonal flexibility: the film keeps pivoting between tense and even gross stand-offs with various giant monsters (all well-designed, and the film does a good job of stretching its budget: only a couple of the CGI beasts look like CGI, and the practical effects are superbly physical and slimy), and goofy, silly character beats, and this keeps it from ever feeling stale.

There are still some small-scale flaws, most notably a propensity for over-editing (if one shot tells us what we need to know, we can generally expect three; this is most ruinous when it shows up during the film's emotional climax), but it's solid enough as a story and a showcase for O'Brien that some wobbly filmmaking technique can't do too much damage. The problem is when the story stops being solid, as it does in a spectacular fashion near the end. It's a clichéd development that has shown up in more than one film of this sort in the past, and here the film does not make it feel fresh; here, it just seems very clumsy and unmotivated, and a violation of the slick humor of the film leading up to that point. It also forces the movie to devolve into an action setpiece that feels like nothing else in the film, and is deeply uninteresting on its own terms. So the Love and Monsters does do the one bad thing that movies should always avoid doing: it ends by leaving a bad taste in one's mouth, for a good 25 minutes or so.

Granting that, it's a charming film up to that point, and clearly in love with the movie-ness of post-apocalyptic and giant monster movies. It's a fun genre sandbox, with a game, lighthearted performance of neurotic ineptitude to make sure that even at its heaviest and most violent, this is still pretty bubbly stuff. It's a fun present for genre fans, not a serious attempt to do something new; but as a fan of the genres in question, it's a present I enjoyed opening.

For more on Love and Monsters, check out Rob & Carrie's interview with director Michael Matthews