Tom Morgan Freeman and his uncle Charlie Randy Quaid are armored truck drivers delivering money from banks in Huntingburg, Indiana, a town overwhelmed by a heavy rainstorm that has forced evacuations. As the pair collect cash under the threat of rising waters, they are ambushed by Jim Christian Slater and his gang—Kenny, Mr. Mehlor, and Ray. Charlie manages to call in the National Guard, but Kenny shoots him dead as Tom escapes, stashing the looted cash in a cemetery to keep it out of reach.
The gang relentlessly pursues Tom, who seeks refuge in a nearby church. Inside, he is mistaken for a looter by Karen Minnie Driver, who knocks him unconscious. Tom wakes up later in a jail cell and tells Sheriff Mike Collig about the gang and the money. The sheriff and his Chief Deputy Wayne Bryce decide to keep Tom locked up and investigate, while Deputy Phil is ordered to escort Karen out of town. Karen later pushes Phil from a boat to return to protect the church, which she is trying to restore.
As Hank, the dam operator, is forced to open a spillway, a giant wave pushes the flood deeper into the town. Tom sits trapped in his cell while water rises around him. Karen rescues him after he’s hidden away in the church and the two of them hide from the gang. Kenny is electrocuted in the chaos. They take cover in a house and are mistaken for looters by the elderly Doreen and Henry Sears, who refuse to evacuate and insist on protecting their property. Henry reluctantly provides Tom with a boat so he can try to reach the armored truck again. Tom resurfaces from the submerged truck only to find the gang holding the elderly couple hostage, and he tells them he’ll reveal the location of the money.
Jim reveals to Tom that Charlie was secretly in cahoots with the gang and never called in the National Guard; Charlie’s death came as Kenny hadn’t been told that Charlie was on the side of the town. Tom discovers the money has vanished. The group is then ambushed by Mike, his deputies, and Hank, who have tracked down Karen and intend to keep the money for themselves.
Mr. Mehlor and Ray are killed in the ensuing firefight, and Jim and Tom manage to escape, taking shelter again in the church. Wayne drags Karen to her house with the intention of raping her, while the others torch the church and even drive their boats through the stained‑glass windows. Karen defends herself, stabbing and killing Wayne. Hank shoots Phil for hesitating to shoot Tom when the chance arose.
The dam’s emergency alarm sounds, heightening the tension. Mike suggests that Tom and Jim should let Hank and himself go with a couple of money bags, but Tom agrees only to a temporary truce as he leaves to try to save Karen. Mike ends up shooting Jim with a hidden revolver, though Jim isn’t seriously injured. Mike and Hank escape in a boat, and Hank is later killed when the sheriff pushes him out and a gas explosion destroys the boat.
Tom finds Karen handcuffed to a banister and frees her. They climb to the roof to escape the rising water, but are cornered by Mike in a boat. Jim appears from behind them and drifts into the scene as well. Mike’s shot disables Jim’s steering, forcing him over the roof edge; the engine breaks off and collides with the sheriff, sending him into the water. Mike tries to shoot Karen while grabbing a money bag, but Tom and Jim shoot the corrupt sheriff dead. As the first responders—the Indiana State Police—arrive, Jim takes Mike’s bag and rows away, leaving Tom to tell Karen that the fire damage to her church can be repaired.
