The movie opens with three college aged men heading in a car down the interstate somewhere in Vermont. The kids are smoking heavy amounts of weed and having a discussion about whether or not if you own a beach property if you own the sand and the water. They are then stopped by officers Ramathorn and Rabbit, who demand their license and registration and ask the guys what they were doing. As they're getting ready to file a report, they're suddenly called away and the men are ecstatic to learn that they're getting off. But then a few minutes later, the cops are back and once again demand their license and registration. But the guys weren't pulled over for speeding. Instead they're pulled over for blatant offenses and drug violations. Officers Ramathorn and Rabbit take the guys into custody and they're being monitored on the radio by Officer Farva. Farva asks repeatedly if he's needed out there. Ramathorn and Rabbit assure Farva that they've got this one. A White Mazda Miata then passes by them at a break neck speed ensuing a high speed pursuit. They then radio Officer Foster - who's taken a siesta and gone fly fishing. They then end at a bar when it's revealed that the driver is another officer - Mac, who's trying to convince the college guys that he's a wanted killer, and sure enough they've bought it.
The next day the officers are gathered at a local mom and pop shop for a breakfast before heading out on the road. Foster makes small talk with an attractive local cop named Ursula. We are then introduced to the local police, who it turns out, don't like the highway cops very much. Ramathorn and the rookie Rabbit are seen having a chugging contest with full bottles of maple syrup. Ramathorn wins by a mile while Rabbit struggles to keep up. They then get in a fight being provoked by local officer Smy. Captain O'Hagan who runs the Highway Dept. enters to put a stop to the fight.
Back at headquarters, O'Hagan is instructing his officers that they're in danger of being cut from the state budget and that they really need to step up their game and start taking things more seriously. Farva pulls a prank on Rabbit involving a bar of soap in the coffee, and their distraction proves the point that O'Hagan was trying to make. Later that day the officers are out on patrol. Foster and Ramathorn decide to play the "cat game" where they see how many times they can casually insert the word "meow" into the conversation.
The next day while at the station, they're tipped off to a 1052. They go to the scene which involves a Winnebago and a dead body inside. What they don't know upon investigating is that there's a dead woman inside face down in a pile of pig food, and a live and extremely angry pig is terrorizing the Winnebago. Ramathorn orders Rabbit to get the crime scene tape, but it turns out that the local police have already beat them to it. Ramathorn gets in a shouting match with Chief Grady over jurisdictional grievances. They then get into a huge fight that ends with punches being thrown.
Back at the station, O'Hagan is furious at his officers and it seems that they've attracted some negative attention in the press because of the Winnebago fight. But Ramathorn and Foster are seen playing another prank on Rabbit involving shaving cream and a locker. Outside, while washing his car, Rabbit and Farva get into it when Farva talks about John Denver winning the country music award, while the guy who was supposed to win lit the award on fire in front of the whole show. He then sets fire to the tape that Rabbit is listening to. Rabbit talks about the incident that got Farva suspended from road duty when he went haywire on a bus full of unruly school kids.
During the weekend, Ramathorn and his girlfriend watch their son in a Little League softball game, and unfortunately the local police have kids on the opposing team. Pranks and hilarity ensue - involving a giant thing of cotton candy that they send to Officer Rando, who seems less than amused and gets into a fight with the guy sitting in the bleachers behind him. While at the game, Foster has another conversation with Ursula and tells her he had a good time at the Winnebago fight. Ursula tells her that he can slug her back, but is instead hit by a foul ball. Officer Foster then goes and heads down to the local station in another attempt to pick up Ursula.
While out on patrol, Ramathorn and Rabbit are then tipped off to a semi that skipped weighing in. This time they try the "repeat" game.That gets them into trouble - the driver, whose last name is Galakanokis, is driving for a company named Bunty Soap. He then locks the officers in the trailer and takes off. Several hours pass until the other officers arrive. Turns out Ramathorn and Rabbit got distracted by somebody doing a repeater. Ramathorn wonders what's inside the rows and rows of boxes in the trailer. They pick one up, and a huge brick of marijuana falls out of it.
Back at the station, they're showing off the huge haul that they got from the Bunty Soap truck. They're then greeted by Spurberry Mayor Timber who assures O'Hagan that he's doing everything they can to battle with the governor's budget committee over who gets cut and why. Ramathorn then discovers that the Bunty Soap company is a fake company and doesn't exist. And that the driver was using a fake name and license. O'Hagan goes over to the local station where he's battling with Chief Grady over his theory that the Winnebago and the Bunty Soap truck are linked. A smug Grady informs O'Hagan that what they're doing is called "routine police work" and not chasing absurd conspiracy theories.
Foster and Ursula finally have their first date. Unfortunately it ends rather poorly when they're locked in the back of Foster's police cruiser and have to have the door taken off. Meanwhile, Ramathorn and Rabbit have picked up two German tourists for driving in a Porsche 100MPH down the interestate. Rabbit begins heavily making out with the incredibly attractive passenger. Ramathorn - who has his son present, tries everything he can to get Rabbit to arrest them. On their second date, Foster places a prank call to the station to get Ursula outside. They then head into the impound lot where they begin making out on the bed of the Winnebago. Ursula jumps on top of Foster and smashes the bed. They then find more bricks of reefer with the same logo on them that they found in the truck. Meanwhile, Mac and Foster attempt to go undercover at the weigh station to get some intel about Bunty Soap but it turns out that neither of them can drive a semi.
While filling up for gas and getting a snack, Farva is out watching speeders while Mac is getting hot and heavy looking at a billboard for a local strip club. His radar then catches a speeder going nearly 110 MPH. It turns out Rabbit took the Porsche for a joyride. Officer Farva returns to the station - where O'Hagan has informed the troops about the fact that they got an official government form to inventory their equipment. This incident with Rabbit was bad timing as O'Hagan takes him off the road and puts Farva back on. Neither Foster, Ramathorn, or Mac want Farva to be their partner. Unfortunately he's paired with Ramathorn.
Farva's new found freedom back on the road proves to be incredibly short lived however. The next day he's out to lunch with Ramathorn at a local fast food place called Dimpus Burger. He attempts to order a "litre of cola", and the clerk, not knowing what that is, manages to anger the easily-angered Farva who gets in a fight with the clerk. As they sit down, Farva realizes that the cook spit in his burger. But the real offense comes when he pulls off a contest tab on his soda and it pours all over him. He then jumps the counter and proceeds to fight the clerk physically.
Farva is arrested and taken to the local police station where he's being berated by the local officers. Grady then dismisses the other officers and tells Farva that he's got a job opening and that Farva would be the ideal candidate. Back at the station, O'Hagan is watching the looping security tapes from Dimpus Burger that clearly show Farva jumping the counter and assaulting the clerk, and is furious at Farva and permanently takes him off the road because it's all over the police banner and making their department look bad. Farva has also been subsequently banned from Dimpus Burger. That night while taking inventory on their equipment, Ramathorn, Mac, Foster, and Rabbit decide to smoke some of the reefer with the German tourist and watch a propaganda video that explains the origin of the monkey character that's on all the bricks of weed that they've accumulated. Farva has been demoted to being O'Hagan's janitor.
Meanwhile, Foster and Ursula have their first public date, but since they don't want anyone knowing that they are together they are seen dressed as bikers, although Foster has a different idea of bikers than Ursula does. Ursula tries to tip Foster off to the fact that her boss and colleagues are up to something that could be criminal but doesn't know what that is yet and wants the Highway Dept. to figure it out, because she's tired of working for them under the conditions that they're treating her as a professional.
The next day they're trying to figure out how they can get their department in front of the governor, who's in town for a whistle stop visit. The officers start formulating a plan that there's more in the Winnebago and that if they can get it in front of the governor that she'll reconsider her plan to shut down the department. Mac tries his hand at the "bulletproof cup" - an elaborate prank created by O'Hagan to get the rookies naked. But instead they used blanks, and not actual bullets.
It's now time for the governor's visit. The troopers put their plan into action. They break into the police impound lot to get the Winnebago and drive it over to city hall where the governor's giving a speech. It's an open bar and Farva proceeds to get as drunk as he possibly can. They were right and Grady leaves the two dumbest officers at the station. They get a call. Outside is a man presumably having sex with a bear. It's actually an elaborate distraction - Rabbit in disguise. As they drive to the place where the governor's speech is held, as they get to the goods, they learn that they've already been had.
That night, as they learn the shut down is unavoidable, they proceed to have one last party at the station and get really drunk. In the locker room, they're stunned to learn that Farva has switched sides and has become a local police officer. Furious, they hog tie Farva and take his cruiser out for a joyride, making a stop at Dimpus Burger and a couple of other places, including Grady's house, where a way too drunk O'Hagan wants to throw down fisticuffs with Grady. Ursula calls them on the radio. She is finally able to tip them off to what Grady and her fellow officers have been up to. Foster thinks that Ursula was the one who told Grady about the extra marijuana in the Winnebago but it wasn't.
They drive to a remote area where they witness a plane that has just landed. Farva finally manages to free himself to stall them. But a drunk Ramathorn ensures Farva that if he helps them, he could be a hero in all of this. As they're watching the events unfold, Grady goes to meet the pilot of the plane which has Canadian designations and identifiers. Ursula meets up with the troopers and tells O'Hagan that she was the one who gave the troopers all those anonymous tips - about the college kids, the Winnebago, and the Bunty Soap company, that they're all linked to her boss. She's grown incredibly tired of the fact that they constantly put her on the radio and give her no field work. The other local officers are then seen unloading more giant bricks of marijuana from the plane into another semi that bears a striking resemblance to the Bunty Soap truck that they pulled over, and they finally figure out that Grady has been using the Spurberry police department to run protection for a huge drug ring. They then enact a plan to arrest the officers which then leads to a huge drunken brawl between the two departments. But unfortunately with no weapons, they search Farva's cruiser for anything they can for a distraction only to find a blow up doll and a few flare guns. O'Hagan is glad to put the handcuffs on Grady and read his rights.
The next day, the troopers are gathered at O'Hagan's house where he is about to read a congratulatory letter from the governor. Unfortunately, despite the good they've done in tearing down police corruption, the governor still plans to shut down the department for good. Several months pass. We see Ramathorn and Foster operating a beer delivery service and are transporting a keg to a college frat party, which is held at the house of the guys that they had picked up going to Canada. They are seen as being rather mean to the former highway patrol men. Ramathorn, tired of their antics, finally pulls off the uniforms that he and Foster were wearing and reveal themselves to be the new local police. Farva, Ursula, Mac, and Rabbit arrive and they have a huge party.
The movie ends with a post credits scene that shows the incident that got Farva suspended in the first place by attacking a school bus full of kids. The incident was caught on the surveillance camera on Farva's police cruiser.