This “American Masters” presentation includes a fascinating one-hour documentary by Cass Warner Spelling focusing on the four Warner Bros., including her gradfather Harry (who suffered a stroke after his youngest brother, the flamboyant Jack L., tricked him into selling the studios to backers who turned the studio back over to Jack). I’m told “The Brothers Warner” will not be included when Warner Home Video puts out “You Must Remember This,” but Warners, which is more interested in its history than any other studio, continues to aggressively commission and acquire works in this area to supplement its DVD feature releases. “The Homefront Collection,” a collection of three musicals including the first authorized DVD of the public-domain chesnut “This Is the Army,” has “Warner at War,” a new documentary narrated by Steven Spielberg that I’m told includes a lengthy look at one of my obsessions, Warners’ pro-Stalin epic “Mission to Moscow.” Warners has also acquired the DVD rights to “Jack L. Warner: The Last Mogul,” an excellent 1993 documentary by Gregory Orr, Jack’s step-grandson that includes rare home movies. It will be included in December’s Ultimate Collector’s Edition of “Casablanca.” In that movie, Gregory’s late mother Joy Page, then a teenager, plays a teenager whose plight prompts Humphrey Bogart to allow her husband (Helmet Dantine) to win at the roulette wheel. Jack had married Joy’s gentile mom — over the objections of the rest of the Warner Bros. — who previously been married to Don Alvarado, a Warners star in the early talkie era. Joy followed suit by marrying a Warner contract player, Gregory’s dad Wm. T. Orr (as he was usually billed), better remembered for heading up Warners’ TV division from its founding in 1955 through the late ’60s. Warners has also sponsored a spendid coffee-table book also called “You Must Remember This,” written by Schickel and George Perry, just out from Running Press. Besides essays that expand on the documentary, it contains hundreds of rare images from the Warner Bros. archives. One of my favorites, from 1934, shows Kay Francis, Warners’ top female star of the ’30s until Bette Davis ecliped her, looking out over a collection of ruined buildings (it’s at left in the two-page spread below). I assumed it was a still from one of her weepies, until I read the caption. It’s a publicity shot of Kay surveying the damage from a major fire on the Burbank lot that destroyed the negatives of most of Warners’ silent films, as well as those of the two companies it had acquired in the ’20s, First National and Vitagraph, and even some of Warners’ early talkies.

By LOU LUMENICK

What do “Little Caesar’’ (1931), “Casablanca’’ (1944), “The Searchers’’ (1957), “Dirty Harry’’ (1971) and “The Departed’’ (2006) have in common?

All went out under the shield logo of Warner Bros., which film historian Neal Gabler says has “a vision of the world that is darker, more cynical and more problematic than any other studio has.’’

“You Must Remember This,’’ a sprawling five-hour documentary by veteran Warnerologist Richard Schickel, that the “Warner DNA’’ of socially conscious, politically provocative and edgy entertainment is still intact in more recent movies like “The Matrix’’ and “Batman Begins.’’

“The studio really hasn’t changed very much,’’ says George Clooney, who has made nine movies for Warners – where he achieved stardom with the TV series “ER’’ – over the past decade, tackling such risky subjects as profiteering during the first Gulf War (“Three Kings’’), American spying in the Middle East (“Syriana’’) the difference between dissent and treason (“Good Night, and Good Luck’’) and legal ethics (“Michael Clayton’’).

Today’s movies from, say, Fox or Universal, have little in common with those the studios released in the 1930s. But interviews with Warner executives from the ‘60s onward make clear they have faithfully embraced the philosophies (and the liberal politics) of the original Warner Bros.

There were four of them – the oldest, Harry was a devout Jew born in Poland and believed in film as an educational medium and served as the head of the company. The youngest was there was the better known and more assimilated Jack, who was a born showman.

“You Must Remember This,’’ which is airing as part of “American Masters,’’ is a fairly frank celebration of Warner Bros.’ history backed by the studio itself, which will release it on DVD in December. It was made to commemorate the 85th anniversary of Warners’ incorporation, though the brothers opened their first theater in Youngstown, Ohio in 1903 and made their first first, unsuccessful forays into distribution and moviemaking by the end of the decade.

A good chunk of time –generously larded with clips and archival interviews going back to the ‘70s — is predictably devoted to the studio’s fabled ‘30s and ‘40s, when Warner Bros. churned out classics with stars like Bette Davis, Errol Flynn, James Cagney, Humphrey Bogart, Al Jolson, John Barrymore and Joan Crawford, as well as the Busby Berkeley musicals.

But the documentary’s greatest value may be in shining a light on the lesser-known gems in the studio’s output, especially the films that pushed the political envelope.

There are two exposes about the Ku Klux Klan – “Black Legion’’ (1937) with Humphrey Bogart, which the Klan unsuccessfully sued for defamation; and the noirish “Storm Warning’’ (1952) which combines the plot of Warners’ “A Streetcar Named Desire’’ with the talents of the studio’s biggest star of the era, thesinger Doris Day, and a longtime Warner contractee named Ronald Reagan.

The brothers defied an unofficial ban against anti-Hitler movies to make “Confessions of a Nazi Spy’’ (1938), covertly agitated for U.S. entry into World War II in various period movies, and, at President Roosevelt’s behest, backed “Mission the Moscow,’’ a lavish propaganda epic that presents Josef Stalin as a twinkly-eyed grandfather figure to promote American’s then-alliance with the Soviet Union. Cited during the blacklist era, the latter movie has scarcely been since since.

It’s easy to laugh at Martin Scorsese’s claim that “The Silver Chalice’’ (1954), a cheesy biblical epic that includes Paul Newman’s movie debut is “a radically imaginative use of widescreen.’’

Narrator Clint Eastwood, who recounts the hard time he had selling even Warner Bros. (which took on a financial partner to share the risk) the Oscar-winning right-to-die drama “Million Dollar Baby,’’ argues more credibly that the Bugs Bunny cartoon “What’s Opera Doc’’ “may be the most perfect film ever made at Warner Bros.’’

Perhaps. But you gotta love any studio that gave Stanley Kubrick a blank check for two decades, backed Steven Spielberg’s striking flop “The Empire of the Sun’’ and such risky-sound projects as “Deliverance,’’ “All the President’s Men’’ and “Dog Day Afternoon’’ – as well as Eastwood’s orangutang comedy “Any Which Way But Loose,’’ the biggest hit of his career.

Here are some key Warner films through the decades:

“My Four Years in Germany” (1918) – The Warners Brothers’ first hit, a propaganda epic made five years before they founded the studio.

“Lights of New York” (1928) – The first all-talkie introduced the term “take him for a ride.”

“Baby Face” (1932) – Still-shocking pre-code drama wherein Barbara Stanwyck sleeps her way up the corporate ranks.

“Taxi!’’ (1932) – Tough hack Jimmy Cagney chews somebody out in Yiddish.

“The Adventures of Robin Hood’’ (1938) – Errol Flynn battles political corruption in Olde England.

“Jezebel” (1938) – Bette Davis scandalizes the old South by wearing a red dress – in a black and white film many swear is in color.

“Casablanca’’ (1942) – Cynical saloonkeeper Humphrey Bogart is shocked, shocked at turn of events.

“Mission to Moscow” (1943) – Pro-Soviet propaganda epic reportedly commissioned by President Roosevelt to support our World War II ally.

“Mildred Pierce” (1946) – Joan Crawford wins an Oscar as the ultimate self-sacrificing mom in a feminist noir.

“Rebel Without a Cause” (1956) – James Dean as a definitive juvenile delinquent; released posthumously.

“The Searchers” (1957) – John Wayne’s darkest role in John Ford’s greatest film.

“A Face in the Crowd” (1957) – Andy Griffith as a phony radio personality in perhaps Warners’ most cynical movie ever.

“Who’s Afraid of Virginia Woolf” (1966) – Groundbreaking use of adult language toppled the old Production Code.

“Bonnie and Clyde” (1967) – Gangster epic pushed the envelope by combining extreme violence and comedy.

“Deliverance” (1972) – Male rape depicted on screen for the first time.

“Dog Day Afternoon” (1975) – Al Pacino plays the first leading gay character in an American studio movie.

“The Shining” (1980) – The only hit among Stanley Kubrick’s uncompromising films for the studio.

“Batman” (1989) – Tim Burton offers an unforgettably dark and striking view of Gotham City.

“Goodfellas” (1990) – Crime epic, arguably Martin Scorsese’s greatest film.

“Unforgiven” (1992) – Clint Eastwood wins Best Picture and Best Director for a bleak revisionist western.

“The Matrix” (1998) – Visionary sci-fi set in an alternate universe