Due to a shortage of police officers, the newly elected mayor of an unnamed American city requires the police department to accept all willing recruits, regardless of sex, body weight, skin color or age. Carey Mahoney is an easy-going man who has repeatedly gotten in legal trouble when standing up to arrogant people; after his latest scrape, Police Captain Reed (who was friends on the force with Mahoney's late father) gives him a choice: enroll in the police academy or go to jail. Mahoney agrees to the former, but plans to be such a bad student that he'll be expelled and can go back to his old life. The chief of police, Henry Hurst, outraged by the Mayor's plan (on sexist and racist grounds) decides the answer is to make the experience so bad for the new recruits that they'll give up on their own.