Slasher horror down in the woods, as three couples try some magic mushrooms - then wish they hadn't. When five American students arrive in Ireland to go camping with their old college friend Jake (Jack Huston), they decide to try out the local magic mushrooms, apparently the best in the world. But after they start tripping, reality and imagination begin to blur, as Jake tells stories of mutilated bodies and unsolved murders. Soon, members of the group start to go missing, and panic sets in when they begin to think something, or someone, is stalking them. But is it all just a case of bad trip paranoia, or is there really a crazed madman in their neck of the woods?