John Cazale

Film fans won't encounter many better-spent 40 minutes than this tribute to actor John Cazale, "The Godfather" co-star who appeared in a mere five films -- all of them, astonishingly, nominated for best picture -- before dying at the age of 42, prior to the 1978 release of his final movie, "The Deer Hunter." Both touching and an informative look at the actor's craft, director Richard Shepard's documentary talks to a who's-who of Cazale's contemporaries as well as younger actors who revere him. Before it's done, he'll break your heart all over again.

Presented by Brett Ratner (who is among those featured discussing the actor), the movie shrewdly opens by asking people on the street to identify Cazale's picture. Those few who can generally name him only as "Fredo," his character in the first two "Godfather" films.

Reminiscing about Cazale brings out the best in his contemporaries, from Al Pacino and Gene Hackman to Meryl Streep (with whom he was involved) and directors Francis Ford Coppola and Sidney Lumet, who cast Cazale at Pacino's urging in "Dog Day Afternoon."

Clearly a labor of love, the project judiciously sprinkles in clips of Cazale's work, while racing through his biography in order to explore his filmography. Various tidbits do emerge, though, including what even Cazale's friends saw as his surprising success with women.

If there's a minor quibble here, it's that Shepard wasn't more generous with scenes from "The Godfather" saga, instead devoting considerable time to younger actors -- mainly Steve Buscemi, Sam Rockwell and Philip Seymour Hoffman -- who drew inspiration from Cazale's performances.

Given the iconic nature of "The Godfather" (the documentary derives its title from perhaps the most memorable scene in Part II), showcasing Cazale's contribution to those films speaks as powerfully as any of the commentary.

For anyone weaned on classics of the '70s, HBO's invitation to "I Knew It Was You" is indeed an offer they shouldn't refuse