The Ruins
In a dark, dungeon-like room, a young woman tries to call for help on her cellphone. Unable to receive a signal, she is dragged away by an unseen force.
Two young American couples (Jeff and Amy, and Eric and Stacy) are vacationing in Mexico. At the pool of their hotel they make friends with a German tourist, Mathias. They decide to help Mathias look for his brother Heinrich, who joined an archaeological dig at a remote Mayan ruin in the jungle.
The location of the ruin is shown only on a crude map that Heinrich drew before departing. They join forces with Dimitri, who is in search of his friend (the girl in the opening scene). After a long bus ride the six adults arrive at the trail head, where they see a jeep, and hike the rest of the way the site.
Shortly after they arrive, enraged Mayan villagers appear armed with guns and bows and arrows. When Amy inadvertently steps into the vines covering the ruin, the Mayans aim their weapons at them. When Dimitri tries to calm the situation down, he is shot and killed. The Mayans force the others to climb up to the temple roof.
There the five find an abandoned camp with a mineshaft in the center. The group try their cellphones but nobody has a signal. Mathias soon finds his brother's body. From the bottom of the shaft, they can hear a cellphone. Mathias is lowered into the shaft but the rope breaks and he crashes to the bottom. Amy descends the temple steps to try to reason with the Mayans. When she angrily throws a clump of vine at them and hits a young boy, the others promptly kill him. Later, Jeff and Eric rig up a backboard and the paralyzed Mathias is lifted out of the mineshaft.
The next morning, Stacy finds that a tendril of the vine has crept into her wound. Even worse, the vines have wrapped themselves around Mathias's lower legs and have eaten into them, down to the bone. The cellphone is heard again, and Stacy and Amy are lowered down the shaft to find it. In a small, vine-covered room they find the body of the young woman and her phone, which is broken. The flowers are vibrating and screeching, reproducing the ring of the cell phone. The vines attack them but they manage to escape. Stacy is convinced the vines are alive, and that they are growing inside her. The group realizes that the vines are predatory and that the Mayans are actually trying to keep them quarantined and have salted the earth all around the hill. Jeff insists that "Americans on vacation don't just disappear" and that help is on the way.
With Mathias' condition deteriorating, Jeff amputates both of his legs. Stacy becomes jealous when she sees Eric comforting Amy, saying that she overheard them having sex. When Jeff comes to try to defuse the situation, Stacy calls Amy's fidelity into question. While the four of them argue, the vines suffocate Mathias.
Later, Stacy finds that the vines are now growing inside her. Jeff is able to cut out two but stops after realizing the futility of his efforts. Stacy claims that she can feel more inside of her but the others reluctantly deny her pleas to remove them, instead saying that she will be fine in an effort to comfort her. While the others sleep, Stacy sneaks out of the tent and begins to cut the vines out herself. When Eric tries to stop her she swipes at him and stabs him through his chest. As the vines move in to take Eric's body, Stacy's cries to be put out of her misery. Jeff removes the knife from Eric's body and kills Stacy.
Realizing that they will both eventually die, Jeff makes a plan for Amy to escape. He carries her down to the bottom of the temple and lays her on the ground making it appear as if she has died. While distracting the Mayans to allow Amy to escape, Jeff is shot. As the vines slowly reach out to him, the Mayan leader shoots him in mercy. Meanwhile, Amy flees the rest of the Mayans, and safely makes it to the jeep and escapes.In the ending scene, 2 new tourist are seen moving towards the temple.
