American cinema from the '70s maintains a sterling reputation for a variety of reasons, most having to do with the decade's flowering of serious, artful, character-driven slices of life. Even early-'70s cop movies tended toward the gritty. Next to 1971's The French Connection, the benchmark '70s police drama is 1973's Serpico, based on Peter Maas' biography of NYPD whistleblower Frank Serpico. Al Pacino (between Godfather movies at the time) plays the title character as a reluctant savior in a Jesus beard; he quietly insists that the police are responsible for staying connected to the people they serve and protect, and he's certain that his responsibility includes not taking payoffs from criminals. The actual Frank Serpico story is gripping, marked by threats from his fellow officers, a suspicious on-the-job shooting, and a courageous appearance on the witness stand at a police-corruption hearing. All of that makes it into the movie, but director Sidney Lumet (working from a screenplay by Waldo Salt and Norman Wexler) chooses not to press the superheroic aspect of his protagonist. Serpico is more street-level, tracing a decade of NYPD changeand refusal to changethrough an episodic, often elliptical structure. As Pacino bounces from precinct to precinct, his integrity paradoxically costs him the trust of his fellow cops, and each segment of Serpico typically begins with the promise of a new start for the hero, followed by a series of incidents which again establish the bitter truth of life on the force. Meanwhile, Pacino's all-consuming disgust sabotages his off-the-job relationships, and leaves him only his martyrdom to cling to. Lumet's smart decision to let the story's inherent drama unfold through a string of loosely connected moments is explained on the new DVD edition via a handful of interviews with the director, whose descriptions of the project's background and development are as good as any commentary track. Unfortunately, the DVD extras lack any input from Pacino, the key to Serpico's success. His sunken eyes and slouching posture give way to a kind of stiffly quivering ferocity when his outrage is strong enough, and his extremes of slumping inaction and semi-spastic action create a unique kind of charisma. That's yet another gift of '70s cinema: that someone as lumpen, intense, and deeply inquisitive as Pacino could become a star.