Philip Roth’s alternate-history novel The Plot Against America came out in 2004. At that time, his story of a populist leader with no political experience coming to power by stoking racial prejudice played a little more like a fantasy than it does now that David Simon and Ed Burns have adapted it into a six-episode HBO miniseries. Roth imagined an alternate 1940, where famed aviator (and noted anti-Semite) Charles Lindbergh challenged Franklin D. Roosevelt in the U.S. presidential election. With a pledge of "America first," Lindbergh promises neutrality in the European war, as the Nazis rampage across the continent, and he emboldens anti-Semitism among the American people.

In Simon and Burns’ version, Lindbergh’s rise to power -- he defeats Roosevelt in the election and becomes president, pursuing policies that further marginalize and harm Jews -- is a clear analogue for the current political climate. "Tonight we have taken back America," Lindbergh says in his acceptance speech on election night. "They’ve always been here, but now it’s like they have permission," Jewish merchant Monty Levin (David Krumholtz) says of the outspoken bigots who are now comfortable expressing their views in mainstream society. The parallels are so clearly laid out that the show often feels more like a political tract than a period drama, with characters who mainly serve as mouthpieces for the story’s competing points of view.

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The novel was structured as a look back on the era by a grown-up Philip Roth, who in the show is renamed Philip Levin (Azhy Robertson), the younger son of Newark, New Jersey insurance agent Herman Levin (Morgan Spector) and his wife Bess (Zoe Kazan). The Levins, including older son Sandy (Caleb Malis), adult cousin Alvin (Anthony Boyle) and Bess’ sister Evelyn (Winona Ryder), are living the American dream as the series begins in June 1940. Herman is up for a promotion and has bought a car. The family might be able to move out of their duplex and into a house of their own in a nicer neighborhood.

But everything changes when Lindbergh starts to gain popularity. Simon and Burns take their time getting to Lindbergh’s election (which happens at the end of the second episode), and in its early going The Plot Against America is a fairly familiar period drama about a working-class minority family. Even after the election, as the plot jumps ahead months at a time, it’s a slow build to the true social chaos, which never reaches the level of Nazi Germany but eventually becomes very dangerous for the Levins and other Jews. Despite the alternate-history premise, this isn’t science fiction like The Man in the High Castle or pulp action like Hunters, two Amazon series that tackle similar what-if ideas about Nazis taking power in America.

As is to be expected from Simon, creator or co-creator of social-realist dramas including The Wire, Treme and The Deuce, The Plot Against America is serious and, well, seriously depressing, but it also doesn’t have the rich tapestry of characters that define Simon’s best work. The focus here is almost entirely on the Levin family and their immediate neighbors and friends. Lindbergh himself (played by Ben Cole) only makes brief onscreen appearances, and the main avatar of right-wing politics is Rabbi Lionel Bengelsdorf (John Turturro), a smooth-voiced orator who becomes Lindbergh’s token Jewish ally. Lionel also ensnares Evelyn, who starts out as his assistant and eventually becomes his wife and confidante, supporting him in the creation of policies including a relocation program that sends Jewish kids from coastal cities to live with rural families in "the real America."

It’s a soft version of the Nazis’ concentration camps, and like everything in the heavy, slow The Plot Against America (with episodes that all run a full hour and sometimes longer), it’s a belabored device that makes the same point over and over again. Simon’s dedication to social commentary can be bracing and righteous when put into the mouths of fascinating, well-realized characters, but everyone in The Plot Against America is defined by their political beliefs and social standing, with little personality beyond a connection to Jewish culture. The Levin kids, central to the novel’s narrative, are often sidelined here in favor of long political arguments between Herman and Alvin (who later flees to Canada to join the British army and fight the Germans). Only Kazan’s Bess exhibits the kind of emotional depth that makes the story more than a piece of timely alarmism.

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As the story’s most prominent antagonists, Ryder and Turturro both give disappointingly one-dimensional performances, and the true cost of their betrayal never really comes across, even when they directly face the consequences. Ryder fidgets and frets as Evelyn, whether she’s complaining to Bess in early episodes about her messy personal life or attempting to support Lionel and his ambitions as the series goes on. Turturro gives the Southern-born Lionel an absurdly exaggerated accent, but his personal motivations are always murky. He serves an important plot function, but never seems any more like a real person than the mostly absent Lindbergh.

On Simon's more open-ended series, character relationships are explored as much as institutional failures, but Simon miniseries like Generation Kill, Show Me a Hero and now The Plot Against America tend to narrow their scope to make a particular point. That point here is sometimes powerful, but it’s also hammered home so relentlessly over the course of six-plus hours that eventually the only response is resigned exhaustion.

Starring Morgan Spector, Zoe Kazan, Winona Ryder, John Turturro, Anthony Boyle, Azhy Robertson and Caleb Malis, The Plot Against America debuts Monday on HBO at 9 p.m. ET/PT.

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