多年前，強盜趁接線員潘美拉上班執勤時闖空門，他們撥打911告知潘美拉失火地點，隨後放火燒屋，女兒凱西因此留下傷疤，潘美拉也因此與當時外出辦事的警察丈夫傑瑞米關係陷入緊繃。只是，她怎樣也料想不到，當年惡夢竟然重演。她再次接到恐嚇電話，明白凱西又落入強匪手中，她被迫不能掛斷電話，也不能向人求救，面對這通追蹤不到來電位置的電話，她將如何與丈夫拯救愛女？

When the daughter of veteran 911 call center operator Pamela (Mischa Barton), and her estranged husband Jeremy (Luke Goss), a Senior Police Officer, is kidnapped and held hostage, they are left desperate, with no choice but to follow the kidnapper"s rules: send messages through dispatch for all police and fire units to scatter to remote locations throughout the city where they are met with chaos. Not knowing who or why, the one thing they do know is if they fail to discreetly collaborate with one another - they will be solely responsible for facilitating the biggest crime in the city"s history. Now they must race against the clock to make the choice of their lives - save the city - or save their daughter.