Two young American couples, while on their last day on vacation in Mexico, decide to accompany a German acquaintance and his Greek friend to a secluded archeological dig that's about twenty miles away. The German is going there to retrieve his brother, who went their with a girl (one of the archeologists). When the group gets there, though, they see some abandoned vehicles and notice that the path to the temple has been hidden by palm fronds. Why is it being hidden? They soon find out when they reach the ancient temple and Mayans from the nearby village come out. The villagers will not let them set foot off of the temple. When one of them tries they shoot him with an arrow. In fact, a large, salt covered perimeter is all around the structure, which prevents the vines from growing into the nearby jungle. It's these vines that are the problem...they are alive and feed on meat.
Fans of the book will be pleased, as it is a good adaptation. There are some slight changes but they are for the better. The Mayan temple is quite the centerpiece of the movie while in the book it's just a big dirt and vine covered hill, implied that the temple is presumably buried underneath). Some of the characters are combined for expediency sake but it's a necessity in order for the movie to move along swiftly. And while the movie has the ending from the book it also has a new ending, which leaves all sorts of possibilities for a sequel. Overall, THE RUINS is a DeVINE horror movie.