In 1983 Mason Storm (Seagal) is a Los Angeles police detective who is investigating a mob meeting taking place by a pier. He spies on them with a video camera and captures on tape a shadowy figure telling the other people that they can rely on his political support, emphasizing this by saying "And you can take that to the bank!" Storm is spotted but manages to get away. Driving home and unaware of another pair of cops listening in, Mason informs first his partner then his friend Lt. O'Malley (Coffin) that he has evidence of corruption, and will be bringing the tape to them soon. He goes into a store to get Champagne and a teddy bear to give to his son. The store is robbed, with one of the robbers shooting the clerk. Mason manages to stop them and afterward goes home, intent on celebrating with his wife Felicia (Bonnie Burroughs). Before he does anything else, Mason hides the tape in a small hole in his kitchen wall. When he goes upstairs, a hit squad composed of corrupt policemen, including Jack Axel (Boswell) and Max Quentero (Richmond), working for the politician, break in. Mason is shot non-fatally at first and his wife is killed. Another shot brings Mason down. Mason's young son Sonny, (Bara) manages to hide until the danger passes. At the same time, Storm's partner is shot by a masked assassin whilst seated beside his window. At the hospital, Mason is pronounced dead. As O'Malley stalks off, a doctor tells him Mason was revived but in a coma. Lieutenant O'Malley informs the medics to tell people that Mason died, and hide is identity under a "John Doe" to prevent anyone from coming back for him later. Mason is set up by the corrupt policemen as having murdered his wife and committed suicide. A montage shows a string of events during the next seven years where Trent has become a powerful and influential US Senator.
One day Mason wakes from his coma. Andy (LeBrock), one of the two nurses monitoring him, makes a phone call, which is intercepted by one of the corrupt police officers who want to see Mason dead. They send Jack Axel to the hospital to finish the job and kill the nurses to whom Mason might have talked. Mason realizes that he is still in danger but his muscles have atrophied to where he can barely use his arms. He manages to get himself to an elevator, and when Andy sees her colleagues killed, she helps Mason escape from the hospital.
Needing time to recuperate, Andy brings Mason to a friend's house in a secluded mountain area, where Mason uses his knowledge of acupuncture, moxibustion and other meditation techniques to recover his strength. While training, Mason hears a commercial for Senator Vernon Trent (Sadler) on television, who caps the commercial with the phrase, "And you can take that to the bank!" Recognizing the voice, Mason now knows who he has to go after to get his revenge and even mocks Trent's phrase by saying "I'm gonna take you to the bank, Senator Trent. To the blood bank!". Mason contacts O'Malley, who comes over with some weapons for Mason. O'Malley tells Mason that his son is still alive - O'Malley took Mason's son in and raised him, sending him to a private school so that he would be out of danger. O'Malley then leaves. However, Senator Trent's men find the house where Mason and Andy are and attempt to kill them, but Mason manages to get them both out again.
Mason then goes back to his old house. Posing as realtors looking to see if the house is one that can be put on the market, Mason breaks through the plaster in the kitchen to retrieve the video camera and tape he'd hidden seven years before. Mason then goes to meet O'Malley in a train station, where O'Malley brings Mason's now teenage son. They do not see each other, because as Mason arrives, O'Malley is already dead having been shot (by Max) after giving the tape to Andy for safe-keeping while providing a distraction for Sonny (Rosencrantz) to get away. When Mason arrives, he sees his son running away from two of the corrupt officers (recognizing one who helped murder his wife). Mason catches up with the men, kills Max and saves his son and decides to go after Senator Trent at his home.
At the Senator's mansion, Mason sneaks in and manages to take the Senator's men down one by one. Mason fights with Axel in the billiard room, ending with him jamming a pool stick into his neck. Mason finally manages to confront Senator Trent and holds him at gunpoint when the police storm the mansion. However, rather than arresting Mason, the police arrest Senator Trent and take him away. Mason is then reunited with Andy and his son and walk off as the image from the videotape is played, showing Trent coming out of the shadows briefly, wondering who it is that is taping him.