影片讲述了一对警察兄弟，弟弟健诚（黄宗泽饰）为卧底，哥哥健忠（谢天华饰）为缉毒警，兄弟俩互在警方和贩毒集团的黑名单上，随着一场押送毒贩的任务，二人卷入其中，展开了一场无间反转的缉毒故事。
The film opens in a bleak police station where celebrated war correspondent Kate Rafter (Seagrove) faces questions from a psychiatrist, Dr Shaw (Kurylenko), as they work through the painful events of Rafter’s life. A horrific incident in war-torn Iraq and the death of her mother (Steed) have brought a haunted Rafter home to Herne Bay, a place she believed she had escaped forever. Her resentful sister (Friel) has not made her sister welcome and her forbearing husband Paul (Miles) fails to broker peace. Whilst packing up her mother’s belongings from her childhood home, Rafter comes to believe there is something strange and terrifying happening in the house next door.
