Durk was first told about the traffic in ""boys shirts,"" ""pants,"" and ""pillowcases"" by the old man who was worried because his kid was moving packages for the heroin bosses of Pleasant Avenue. Durk checked it out: Caddys and Lincolns double-parked along the Avenue; cops selling guns to the young toughs making deliveries. The local precinct was out to lunch. With mounting anger Durk became convinced that the elite Special Investigation Unit of the Narcotics Division was acting as a heroin brokerage. But this was 1969 and the Lindsay people had their minds on reelection: ""All I was getting was more bullshit."" So Durk began talking to the press and the Knapp Commission; he became one of the Commission's star witnesses. He lacks the glamor of Serpico and nobody ever tried to knock him off--but he was instrumental in cleaning up the police force and launching Operation Uncover, which, in 1973, indicted 86 hoods, including the kingpins in the Pleasant Avenue heroin establishment. He gets a mite sentimental when thinking of the old man with whom he kept faith. But what comes across best is his anger toward the ""poverty pimps"" and the ""sophistry and cant"" of the Lindsay administration, which he blames for writing elegant press releases while ""hundreds of lives and police careers"" went down the drain. It's a solid story, written with no tough-guy bravura and no chest thumping; why did he wait so long to spill it?