The patients and staff of a secluded heroin treatment center must do battle with more than their own demons as a mysterious killer begins picking them off one-by-one.

根据英国童话作家肯尼斯·格雷厄姆（1859～1932）的《柳林风声》改编而成，描写了河鼠、鼹鼠和獾千方百计帮助癞蛤蟆改正懒惰、自大等缺点，融入动物快活的生活的故事。