The Scottish Highlands: a sparse, mountainous region some say was carved by the gods themselves. Few places are as untouched as this harsh, prehistoric landscape. It is no place for man. But nestled deep within the wilderness lies a cottage, and behind that cottage is a hill....

Once every year, Scoutmaster Tim Riggs leads a troop of boys into the Canadian wilderness for a weekend camping trip - a tradition as comforting and reliable as a good ghost story around a roaring bonfre. The boys are a tight-knit crew. There’s Kent, one of the most popular kids in school; Ephraim and Max, also well-liked and easygoing; then there’s Newt the nerd and Shelley the odd duck. For the most part, they all get along and are happy to be there - which makes Scoutmaster Tim’s job a little easier.

The Ruins follows two American couples enjoying a pleasant, lazy beach holiday together in Mexico. On an impulse, they go off with newfound friends in search of one of their group, the young German who, in pursuit of a girl, has headed for the remote Mayan ruins, site of a fabled archeological dig.

This forest isn't charted on any map. Every car breaks down at its treeline. Mina's is no different. Left stranded, she is forced into the dark woodland only to find a woman shouting, urging Mina to run to a concrete bunker. As the door slams behind her, the building is besieged by screams. Mina finds herself in a room with a wall of glass, and an electric light that activates at nightfall, when the watchers come above ground. These creatures emerge to observe their captive humans and terrible things happen to anyone who doesn't reach the bunker in time. 

Once you get it, you simply cannot stop screaming. You can’t eat or sleep. It drives you more and more insane until you can’t stand to be alive a second longer. When the phenomenon hits Chuck's city, the chronically unemployed pervert joins a band of misfits to make his final stand.