In his grizzled author photo, Leuci still looks a little like a longer-haired Treat Williams, who played the truth-telling NYPD narcotics cop in 1981's ''Prince of the City.'' This memoir is his own accounting of his ascension through the ranks and his extraordinary ordeal as he -- occasionally working alongside future mayor Rudy Giuliani -- helped blow the lid off corruption in New York's criminal justice system. Here, though, the movie-friendly story of Leuci's whistle-blowing bogs down in slack pacing and too many names. What really sings is the more familiar yet punchily assembled first part of the book, as young Leuci (a.k.a. ''Babyface'') busts dopers, cultivates informants, and struggles against succumbing to ''the collective nervous breakdown of the system.''