The film opens with archival footage from a press conference where NYPD officers Dave Greenberg and Robert Hantz are being commended by Commissioner Patrick V. Murphy for the sheer volume of drugs and weaponry that the two cops have removed from the streets.
After a credits sequence, the narrative begins at the New York City Police Academy, where Greenberg (Leibman) and Hantz (Selby) graduate as probationary officers. They are assigned to low-level work like clerical tasks and directing traffic, but they chafe against the insignificance of these tasks and frequently abandon them to follow the sound of gunfire. One day, Greenberg is standing on the street in plain clothes when an elderly man offers to sell him some “French films” (porn). When he refuses, the old man attacks Greenberg, who arrests him. Greenberg gets in trouble for making an arrest while off-duty.
Greenberg and Hantz decide to keep making off-duty collars. They go to Coney Island disguised as Texaco attendants. They make a drug bust under the boardwalk and bring their collars to the local precinct, where the supervising officer is astonished to learn that two off-duty probationary cops confiscated so many illegal weapons and drugs. The pair continue to make busts around the city in their spare time. They stop a stolen car on Convent Avenue in Harlem, and at the local precinct, they bluff their way into being treated as senior officers from the “SUB” division, which is just the acronym for traffic enforcement.
After their probationary period, they are assigned to the fictional 21st Precinct in the Bedford-Stuyvesant neighborhood of Brooklyn. On their way to report for duty, they are aghast at the state of the neighborhood, and the precinct seems to be in just as much disarray. They are told to not make waves and to report for their first full day of duty the following morning. Instead, they find some prostitutes, hoping to get information. Greenberg tells his prostitute, Sara (Frazier), that he is a cop and asks where he can find some drug dealers. She screams for her pimp, causing a commotion.
Undaunted, Greenberg and Hantz manage to find an informant and make their first drug bust. As they book their collars, they identify themselves as new to the precinct. They are asked when they started, and Greenberg replies, “Tomorrow”. They track down the precinct Captain Krasna (Frazer). He is convinced his office is bugged, and he views Greenberg and Hantz’s enthusiasm warily.
Greenberg meets Sara again at Hank’s Tip Top Inn and accompanies her back to her apartment. He presses her for information about drug activity. The duo start making busts with her information. Captain Krasna calls them into his office and accuses them of being on the take because of all their independent drug busts. He pretends to call Internal Affairs, but when they do not react like corrupt cops, he decides to encourage their freelancing. Sara tells Greenberg that a contract has been put out on them. An anonymous tip to the station confirms her warning. Greenberg and Hantz lay in wait for their assassins and make a daring bust in broad daylight. The bystanders jokingly yell out greetings to the adventurous cops who they call “Batman and Robin”.
At the arraignment for the case, Greenberg and Hantz are offered $1,500 to lie and get the case dropped. They try to gather evidence about the attempted bribe, but the District Attorney’s office ruins the bust by warning off the targets. The officers are growing more isolated by their fellow cops, who either resent them for showing them up, or view them with suspicion as being either corrupt or part of Internal Affairs.
The partners eventually corner the three Hayes Brothers who run the drug market in Bed-Stuy. The Hayes offer them a $1,000-week bribe, which Greenberg and Hantz pretend to take. Greenberg insists on meeting the Hayes’ suppliers, but on the way to the meeting, one of the Hayes notices Greenberg’s wire. Greenberg and Hantz kill the brothers in self-defense, and they are taken off duty while Inspector Novick (Hingle) conducts an internal investigation.
Greenberg is approached by another officer who has just transferred from the 80th Precinct. He offers to cut Greenberg and Hantz in on a scam. They meet at the Fish Delight Hut to discuss the details. It turns out the officer is from the Knapp Commission, and when he tries to arrest Greenberg and Hantz, the pair, in turn, try to arrest him for engaging in conspiracy. Greenberg threatens to arrest the other Knapp officers on the scene for entrapment. When Insp. Novick and Cpt. Krasna arrive at the restaurant, both factions of officers reveal that they have been taping each other. The stalemate is resolved by promoting everyone. The film ends with a re-enactment of the opening press conference, with Novick commending Greenberg and Hantz for their service.