Bob Lee Swagger reluctantly leaves a self-imposed exile from his isolated mountain home at the request of Colonel Isaac Johnson, who appeals to him to help track down an assassin who is planning to shoot the president. Johnson gives him a list of three cities where the President is scheduled to visit and Swagger assesses a site in Philadelphia as the most likely. This turns out to be a set-up; while Swagger is working with Johnson’s agents to find the rumored assassin, the Ethiopian archbishop is instead shot while standing next to the president. Swagger is then shot by a police officer but manages to escape. The agents tell the police that Swagger is the shooter and stage a manhunt for the injured sniper. However, he meets a rookie FBI special agent, Nick Memphis, disarms him, and steals his car. After his escape, Swagger takes refuge with Sarah Fenn, widow of his late spotter and close friend, killed years before in a mission in Africa. He later convinces her to help him contact Memphis with information on the conspiracy. Memphis is blamed for Swagger’s escape and is informed that he will face disciplinary review but argues that, given Swagger’s training and experience, it is surprising that the president survived and the archbishop standing several feet away was killed. He independently learns that Swagger may have been framed for the assassination and is further made suspicious when he learns that the officer that shot Swagger was himself shot dead just hours later in a mugging. When the agents realize their secret is compromised, they kidnap Memphis and attempt to stage his suicide. Swagger tails them and kills the captors. The two then join forces and visit a firearms expert who provides information on the FBI’s ballistics report and a short list of people capable of taking a shot from a distance of one mile or more. Armed with this, they plot to capture the ex-sniper who they think is the real assassin. Once they find him, he commits suicide after revealing that the archbishop was actually the real target and was murdered to prevent him revealing U.S. involvement in the massacre of an Eritrean village. The massacre was carried out on behalf of a consortium of American corporate oil interests headed by corrupt Senator Charles Meachum. Swagger records the ex–sniper’s confession of his involvement in the African massacre and then, with Memphis’ assistance, escapes from an ambush by mercenaries. Meanwhile, other rogue mercenaries have kidnapped Sarah to lure Swagger out of hiding. With his new evidence and cat and mouse strategy, Swagger and Memphis are able to rescue her when Colonel Johnson and Senator Meachum arrange a meeting to exchange their hostage for the evidence of their wrongdoing. The Senator is allowed to escape, while Swagger and Memphis surrender to the FBI. Later, Swagger is brought before U.S. Attorney General Russert and the FBI director in a closed-door meeting with Colonel Johnson, Memphis, and Sarah also present. Swagger quickly clears his name by loading a round into his rifle (which is there as evidence since it was supposedly used in the killing), aims it at the Colonel and pulls the trigger — which fails to fire. Swagger explains that every time he leaves his house, he removes the firing pins from all his guns, replacing them with slightly shorter ones, thus rendering them inoperable until he returns. Although Swagger is exonerated, Colonel Johnson cannot be charged with his crime as the Eritrean massacre was outside American legal jurisdiction. The attorney general tells Swagger that he himself must abide by the law. “It’s not the Wild West where you can clean up the streets with a gun, even though sometimes that’s exactly what’s needed.” Russert then orders Swagger released and exonerates him of all charges. Afterwards, as Johnson and Senator Meachum plan their next move, Swagger breaks in and kills both conspirators, arranging for the house to blow up as if by accident. In a final scene, he drives away with Sarah.
一位軍中最厲害的狙擊手:包伯·李·史瓦格。在一次任務中出了差錯，搭檔不幸陣亡，史瓦格隨後就退役隱居山中，直到一個名為強森的退役上校請史瓦格出來保 護總統的安全，史瓦格同意幫忙，還四處查看地形、風向、風速等有關狙擊的參數。之後回到深山中練習射擊，就動身前往會面強森。 他們藏在在一個空房間，總統隨即進入演講場地，之後衣索比亞得主教也進入會場發表演說，突然一顆子彈打中主教，史瓦格一轉頭，一名被買通的警官對他開槍， 史瓦格中彈後逃跑。途中遇到一位FBI菜鳥探員: 尼克·孟斐斯，史瓦格搶了他的槍和車逃跑，之後被包圍時將車開進河中，史瓦格則游泳逃逸，途中用他在軍中所學的知識療傷，並發現他已經變成全國通緝犯。 史瓦格跑到以前搭檔的老婆:莎拉·芬家中，莎拉幫她處理傷口。而史瓦格在痊癒後打算反擊，叫莎拉暗示尼克偵辦方向。途中史瓦格被兩名警察盤查，史瓦格打昏 他們後逃跑。 而尼克一直努力查槍擊案，並認為史瓦格不是兇手。最後他發現兇手用的是遙控裝備，但隨即就被武裝份子綁走，並不斷用刑，就在他們要處決尼克時，史瓦格在小 船上將他們一一擊斃，救了尼克。 死裡逃生的尼克，加入了史瓦格的反擊陣線，他們跑去拜訪一個軍武知識豐富的老人「智慧(Wisdom)」，發現強森一行人使用「紙包法」，讓彈殼上的膛線 痕跡可以符合另一把槍，還問出一位已經殘廢的高手，史瓦格決定去找他問個明白。不過他也知道是個陷阱，所以做了許多準備:自製出燃燒彈、高爆彈、煙霧彈 等，還給尼克做了狙擊訓練。 到了目的地，史瓦格摸掉了所有哨兵，順便把炸彈擺定位，順利見到那位高手，他說出強森背後的主使者，是一個蒙大拿的參議員後就自殺了。而史瓦格錄了音當作 把柄，不過對方增援部隊也抵達，史瓦格和尼克殺出重圍，還擊落了一架直升機，逃出生天。 而強森一夥人為了引出史瓦格，派人前往綁架莎拉，莎拉持散彈槍抵抗擊斃一名綁匪，但還是被綁走了。 史瓦格得知後，雙方便約了地點會面，強森派人狙擊史瓦格，不料出現的卻是尼克，子彈被裝甲檔住。狙擊手也一一被史瓦格擊斃，一位綁匪拿莎拉當肉盾，手卻被 史瓦格打爛，這時他才露臉。 就在雙方碰面時，FBI出現，史瓦格燒掉了錄音機就地投降。 逮捕歸案後，史瓦格要求召開了聽證會，在問明他的狙擊槍完全沒用過後，史瓦格裝上一顆子彈瞄準強森並扣下版機，結果發現根本無法擊發。一旁的尼克也擺出強 森在衣索比亞屠殺平民的影像，不過由於事發國外，美國本身無法管理。而史瓦格也當場釋放。 就在強森和蒙大拿的參議員在家中飲酒作樂時，一具衛兵的屍體掉下來，強森起身要逃被打死，車子也被炸掉。此時史瓦格躲在屋子下方，靠聲音來源判斷位置，開 槍打傷一個隨從，一名衛兵對地面開槍掃射，史瓦格卻在門口把他擊斃，也打死受傷的隨從，參議員掙扎地從地上爬上椅子，大罵史瓦格大膽，史瓦格則以一顆子彈 做回應。之後把槍放在強森手中，並把房子炸了毀屍滅跡，跳上莎拉的車離開。