On the Miramax Home Entertainment release of Il Postino (The Postman), the director, Michael Radford, delivers a revelatory commentary track. He describes his strategies for imparting the film's themes, his work with the cast and the crew, and the logistics of the shoot, but he also delves extensively into his work with comedian and star Massimo Troisi. Troisi first had to be guided by Radford in modifying his instincts as a comedian for the dramatic part he was playing (as a postman who develops a relationship with a poet on a small Italian island), but then the actor's heart condition flared up, production was shut down, and, when he returned, Radford just managed to complete the footage he needed for the movie before Troisi passed away.

This [close-up] was shot in that last day of pickups that we did on the last day of Massimo's life in the studios here. And there's one little thing that you'll notice here, which nobody, nobody ever notices in the cinema, and that is, there's a moment where the life ebbs from us and then comes back in again. This is where you see that this is a man, an actor, who's going to die, and I'll show you precisely where it is. He's listening here to this thing, he's smiling. He's doing the timing. I'm getting him to do a few things, and I lay in the sound later, so he's actually doing it blankly, he's just doing it in a vacuum. I'm just getting him to run through a gamut of things, but in a moment his eyes start to blink and you'll see his eyes almost shut, as though he's about to fall asleep--there--and then he comes back. And that is a man who is holding onto life with a tiny, tiny thread.

Watching the film, you may be vaguely aware of what happened to Troisi during the shoot, but it is only when you've gone through the entire feature listening to Radford describe his work with the actor, and how poignantly it coincides with the film's story, that when the dedication appears at the end, right before the credit scroll, "To our friend Massimo," it hits you like a bittersweet sledgehammer.

Commentary tracks began, in a trickle, during the earliest days of laser video discs, thanks to the capability of the video disc format to isolate either half of a stereo audio track. In 1984, film historian Ronald Haver recorded an enthusiastic talk to accompany the Voyager Company's Criterion Collection release of King Kong, and in 1987, James Stewart was interviewed by film archivist Paul Lindenschmid on MCA Home Video's release of Winchester '73.

By the time DVDs, which have a more advanced structure of multiple isolated audio tracks, first appeared on the market in 1997, the commentary format was well established as film scholars, film critics, film directors, movie stars, producers, screenwriters, other crew members, and even fans recorded talks to accompany films they had worked on and films...