Scott Smith's ("A Simple Plan") terrifying novel comes to the screen in this nerve-jangling thriller, as two couples on the last leg of their vacation in Mexico leave their comfortable resort to explore ancient Mayan ruins. An armed group of natives prevents them from leaving, forcing them towards a majestic pyramid encircled by vines of the flesh-eating variety. Jonathan Tucker, Jena Malone, Shawn Ashmore, and Laura Ramsey star.