Monsters

For a budget of like six dollars, Gareth Edwards wrote, designed, directed, photographed and did the effects for “Monsters” all by himself. Maybe the budget was a little higher, but not much. The main thing about “Monsters” is its DIY ingenuity.

The effects consist of wrecked city buildings, mislaid multi-ton vehicles and strange, huge, faceless, amphibious, tentacled, bioluminescent beasts with no innate antipathy toward humans other than that which results from being made to feel unwelcome. True, they do go marauding now and again (hence the wrecked buildings and mislaid vehicles), but more often than not it seems like the human casualties are merely those who get in the way.

But perhaps this implies more monstrosity than the movie actually delivers; discretion is a big part of its DIY ingenuity. The pretext — extra-terrestrial life discovered, samples gathered and spilled, monsters hatched, Mexico quarantined — could be a movie or a miniseries unto itself. Hopefully the inevitable swelling of Edwards’ head and budget won’t portend prequels.

His stars are Scoot McNairy and Whitney Able, and with names like that, they had no choice but to do something creative together. If not a movie, at least a band: They could be the next Lindsey Buckingham and Stevie Nicks, leaving us to wonder upon first introduction which is which and who has what gender and whether they are or were involved in real life.

McNairy’s the male and yes, apparently they were. Anyway, in “Monsters,” he plays a reedy, sulky young news photographer, and Able plays the pouty blonde young daughter of his wealthy tycoon boss, who’s assigned him to gather her from a South American retreat and escort her around the “infected zone,” back home to the United States. Well, the around part doesn’t really pan out; they have to go through.

There will be biohazards. Also: backstories, and bonding, and a bloom of potential romance. Sure, it’s derivative, but from sources of such variety that in this case derivation seems strangely like elaboration: “Cloverfield” meets “District 9″ meets “The Road” meets “Before Sunrise”? Wha? Edwards isn’t exactly trying to reinvent any wheels here. He just wants whatever wheels he spins to be his own. He’s sure got some clever effects and some handsomely photographed vistas. And there’s a nice touch in the repeated reference to duck-and-cover gas-mask drills, so pointedly suggesting a xenophobic, resignedly militarized status quo.

As for performance, an amateurish air hangs over the proceedings, but it gives a sometimes helpful sense of naturalism. None of the movie’s other earthlings are professional actors, and even its two stars seem a little rough around the edges. Yet they’re enjoyably plausible in their roles: He’s unseasoned but vaguely ambitious, she’s spoiled but dissatisfied; she wonders if he has ethical difficulty with his job, he wonders if she even has a job. And they’re both understandably just a little out of sorts, what with the looming monsters and all.

Their dialogue seems half-improvised, and sometimes it’s the wrong half. Conversation tends to come from nowhere and go nowhere, yet also to seem conspicuously strategic about hitting certain theme points along the way. Edwards has a good instinct to spread this talk out as the monster-dodging trek advances from one moody locale to the next, but that only seems to highlight how clunky it all is.

“Monsters” works best in the down time between its plot points, as during Able and McNairy’s simple and connective nonverbal exchanges, or when they’re hanging out around the campfire with their armed Mexican escorts, learning about alien egg sacs in the trees and perfunctory American chemical-weapon strafes as best they can given the language barrier.

However high his concept, Edwards’ key is resolutely low. By some aficionados of noisy sci-fi spectacles, his film may well be met with a resounding “meh.” Others surely will liken him to the hungry, scrappy, undaunted young Turks of an earlier generation: Lucas, Spielberg, Cameron. That might be a mixed blessing. In any case, this is an auspicious moment in an impressively self-made career. Let’s hope it hasn’t created a monster.