Police officer Alex Murphy is murdered by a gang of criminals, but subsequently revived by the megacorporation Omni Consumer Products (OCP) as the superhuman cyborg law enforcer RoboCop.

Officer Alex Murphy is stationed at Metro South until his ill-fated reassignment to Metro West.

At an executive meeting, OCP Senior Vice-President Dick Jones presents his new law-enforcement droid, the ED-209, but the droid malfunctions, blasting junior executive Mr. Kinney to death. Bob Morton, another junior executive, takes advantage of the tragedy to pitch his "RoboCop" program directly to the CEO, who gives it the green-light.

He is programmed with three Prime Directives: serve the public trust; protect the innocent; and uphold the law.

Murphy and his partner, Anne Lewis, pursue a crew of thugs fleeing a robbery to an abandoned steel mill. Inside, Murphy is brutally executed by the notorious gang leader Clarence Boddicker and his men, who are responsible for the recent 'cop killings' plaguing Old Detroit.

OCP isn't interested in rebuilding the crime-infested city of "Old Detroit" but plans to replace it with a modern settlement it calls Delta City--an efficient, clean and harmonious city, maintained and serviced by OCP and its subdivisions, an unending project with unending rewards, policed by ED-209s, RoboCops and the OCP-funded Detroit Police Department.

Although RoboCop has only limited memories of his former life as Alex Murphy, he retains the habit of twirling his pistol before holstering it--a skill he had learned to impress his son.

As time passes, RoboCop regains more memories of his previous life, triggered in large part by his incidental arrest of Emil Antonowsky, one of Boddicker's thugs and a participant in Murphy's murder. RoboCop begins pursuing Boddicker's henchmen, finally capturing Boddicker himself after a gunfight in a drug factory and learning that he works for OCP Senior Vice-President Dick Jones.

All that stops RoboCop from killing the helpless Boddicker is his programming, specifically Directive Three: "Uphold the Law". Instead, he takes Boddicker to the station and marches off to arrest Jones. In the process, he discovers a previously-hidden part of his programming. Directive Four: "Never Oppose An OCP Officer".

The final confrontation with Boddicker ends with RoboCop stabbing him in the throat with a computer data spike installed in his fist.