A space probe returns to Earth, crashing into the jungles of Mexico and unfortunately bringing with it alien life. These alien creatures take to their new environment quite well, growing and reproducing and flourishing. Six years later, both the Mexican and the U.S. military are still fighting to contain the creatures, trying to keep them in an "Infected Zone" that basically covers the top third of Mexico, running up to the southern U.S. border. As the movie starts, somewhere further south, "San Jose, Central America," a monster has surged out of the Infected Zone into a small city and the military orders an air strike, killing the creature but also killing a lot of civilians, including tourists in a hotel. Photographer Calder (the wonderfully named Scoot McNairy), down there on assignment to try to get a shot of a live alien, is ordered to track down the wayward daughter of his magazine's owner (Sam, played by Whitney Able) and get her back to the U.S. He does so, reluctantly, and they slowly get to know one another as they make their way up to the border of the Infected Zone. There are two ways across to safety in the U.S.: by ocean-going ferry, in relative safety for $5,000 per person, or by river boats and dirt roads across the Infected Zone itself. I bet you can guess which route they end up taking.
Here's the thing. Monsters is not at all scary. I wouldn't have even included it in this series except for the fact that I am bound and determined to watch more movies this October than I did last year and by the title alone I thought it was going to be a monster-genre horror movie. The critters are pretty well-done: all CGI, of course, but with a bit of a Cloverfield-vibe in that you basically just see bits and pieces and tentacles and not the whole critter. Calder and Sam become characters that you get invested in, having distinct personalities and some character development. No other character gets a name and they, of course, are monster fodder. There is some destruction and some post-destruction bodies but at no time do you ever worry about the two main characters. Monsters is a well-done enough creature feature (for all that you scarcely see the creatures) but a horror story it is not.
50 minutes ago