故事發(fā)生在神秘而又變幻莫測的蔚藍大海之中，凱特（哈莉·貝瑞 Halle Berry 飾）是一位擁有“鯊魚語者”稱號的資深潛水員，從業(yè)近十年，她不僅獲得了業(yè)界的廣泛認可，更靠著自己的努力奮斗擁有了摯愛的漁船——沃蘭特號。
　　一場意外事故的發(fā)生讓凱特幾乎失去了一切，其中包括深深信任著她的搭檔，巨大的打擊令凱特一蹶不振，她拒絕再潛入海底，整日沉浸在悲傷和后悔之中。凱特的消沉直接影響到了她的生活，負債的不斷增加最終將讓她失去沃蘭特號。在好友杰夫（奧利維·馬丁內茲 Olivier Martinez 飾）的牽線搭橋下，凱特決定同一名商人一起重新回到崗位之上，這一次，她要挑戰(zhàn)的是所有潛水員皆聞其色變的危險地帶——鯊魚港。

　　Old miss Marple is on a train ride when she witnesses a murder in a passing train. She reports it to the police but they won't believe her: since no body can be found there can't have been any murder, right? As always, she begins her own investigation. The murder was committed while passing Ackenthorpe Hall and miss Marple gets herself a job there, mixing cleaning and cooking while searching the house for clues.