This weekend, as “Gangster Squad” was opening to poor reviews and poorer box office, I watched a documentary called “Public Enemies: The Golden Age of the Gangster Film.” I'd never heard of it but there it was on Netflix. For, like, free. Narrated by Alec Baldwin. You worry you're going to wind up with some AMC Biography crap but this thing was decent.

It is what it says it is. Its focus is on the 1930s Warner Bros. gangsters: Robinson and Cagney in the 1930s, then Bogart's work from the 1940s. It includes Martin Scorsese as talking head and some of his films. But it never mentions “The Godfather,” at least not so as I remembered, and pretty much ignores the 1950s on. It ends more or less with Cody Jarett. Top of the world, ma.

But the best part of the doc for me was the first 20 minutes when we got clips from silent gangster movies. Not just “The Musketeers of Pig Alley” (1913), which Scorsese talked up in “A Personal Journey with Martin Scorsese through American movies,” but a 1906 silent film called “The Black Hand.” Any “Godfather” fan immediately perks up. “The Black Hand” at the time of Vito Corleone's battle with the Black Hand? Sign me up.

Turns out it's one of about a half-dozen silents with “black hand” in the title. We don't get the others. But we do get these:

Some of “Regeneration” was apparently filmed in Five Points, only 50 years removed from when Martin Scorses would set it in “Gangs of New York.” He watched it as preparation.

There's also a great, short appreciation for Lon Chaney, the man of a thousand faces, who projects powerful ones here. It makes me want to see more of his work.

Why did gangster movies prosper with talkies? Some say it was the sounds, such as machine guns, but you could get those in war movies, too. Others mention the patois, the accents, from the various neighborhoods in New York. Wise guy, see? There's Prohibition, during which most of us became criminals and criminals became powerful, and the Great Depression, when many Americans realized what a scam it all was, and a man making his rise by any means necessary, and in the face of the real criminals, the Wall Street types, was a comforting 90-minute wish-fulfillment fantasy for many Americans.

Plus the movie stars who showed up: Cagney, Bogart, Edward G. Robinson:

By the way, and appropos of nothing, doesn't this actor in “Musketeers of Pig Alley” remind you of Mark Strong?

History written with lightning has simply become history. The backgrounds alone in these early silents, filmed in various locations in New York in the 1910s, make them worth watching.