Teenager James Greville has lived in children's homes his whole life, so he is surprised when a Great Uncle invites him to his country manor for a holiday. While exploring the sprawling Greville Lodge he soon discovers that it has many secrets.

When Detective Mortimer Shade is somehow killed in a freezer, a parasite called a grail possesses his body, revives him, but he needs blood to stay alive. His partner John Dark accepts the new situation and together they become vigilantes, judging and killing the bad guys, with Shade sucking their blood with his claw. However, Dark notes that Shade is losing the rest of his humanity and becoming a monster, being aware and afraid of the danger Shade represents to mankind and trying to stop him.

宾果（Ciaran Joyce 饰）、列妮（Amy Harvey 饰）、保罗（Jonathan Jones 饰）、乔西（Darren Evans 饰）、本（Christopher Conway 饰）和马格西（Ryan Conway 饰）是六个年仅14岁、喜欢惹是生非的青少年。某天，他们逃课，相约来到森林中游玩。本与保罗在林中骑着摩托飚车，结果撞到了名叫彼德（Kevin Howarth 饰）的神秘男子。事后他们与彼得结伴同行，谁知却展开了一段奇异且危险的旅程……
本片荣获2008年英国艺术电影电视学院奖（BAFTA）最佳新人奖、2008年圣克鲁兹电影节评审团大奖、2008年西雅图独立电影节最佳儿童表演奖（Ciaran Joyce）。