Peterloo is, in essence, what happens when Mike Leigh makes a Ken Loach film, and it's also a costume drama. If you are anything like me, you have already perhaps decided that it is clearly the best movie of the 2010. In which case, I am sorry to have to splash some cold water on your and my shared dreams. It's not that Peterloo is bad, not at all; it's just that rabid leftist political agitprop, Loach's bread and butter, proves to be a bit of a rough match for Leigh's actors-and-characters-focused approach to letting stories coalesce out of several otherwise isolated moments of human behavior. Put more clearly: Peterloo is a little bit boring, and this is almost by definition something agitprop shouldn't be.

The film's title gives the game away: this is a dramatic re-imagining of the Peterloo Massacre of 1819, in which an enormous crowd of protesters gathered in St. Peter's Field in Manchester, only be mowed down by a cavalry charge ordered by the local magistrates with the full faith and confidence of the national government. Technically, that's a spoiler: the rally occupies only about the last 20 minutes of the 154-minute film, and the massacre itself only about half of that time or less. The preceding two hours are devoted that most quintessential pastime of Regency England, elaborate discussions about oratorical practice. The enormous ensemble includes several different groups: the government officials both in Manchester and London concerned about the burgeoning spirit of rebellion brought on by the restrictive Corn Laws put into place following the end of the Napoleonic Wars; the local radical groups hoping to foment that exact rebellion; some of the individuals and families crushed down by the Corn Laws and ready for a massive upheaval; and occupying kind of a central place, though only after the midway point or so, legendary orator Henry Hunt (Rory Kinnear), whose much-ballyhooed arrival in Manchester serves as the catalyst through which all of the other characters' various subterranean fears are thrown into open conflict.

Like all Mike Leigh films, Peterloo is blessed by an outrageously good cast, made up mostly of stage and TV actors (Kinnear and Tim McInnerny, playing a revoltingly pasty Prince Regent George, are the biggest "names"), all of them working through the writer-director's usual process of workshopping the material of the screenplay out of the basic scenario and incidents he's given them. That's an even more impressive feat here than it usually is in Leigh's cinema, given that Peterloo takes as its primary subject the highly idiosyncratic way that communication happened in early 19th Century England. Other than the rural family led by Nellie (Maxine Peake, the primus inter pares of this amazing cast) and Joshua (Pearce Quigley), recently destablised by the return of badly traumatised son Joseph (David Moorst) from the war, nobody in this movie just talks They're all of them using language as a tool, a weapon, or a means of social advancement; much of the drama of the first two hours consists of watching people in meetings, negotiating the complicated dynamics by which "correct" public speaking was done in those days. Without exception, every single cast member finds a path right to the heart of what that meant for their characters as leaving, breathing humans, with tangible hopes and frustrations. It's a cliché to talk about historical dramas bringing the past back to life, but I can't think of any other way to describe this, watching as one actor after another launches into minutes of mannered diction not because it's a fun actorly challenge, but because they've correctly identified this as how their character think.

So far, so great, and very much of a piece with Leigh's other two period films, 1999's Topsy-Turvy and 2014's Mr. Turner. Like those films, Peterloo does not modernise a bygone era, but treats its people with the same absolute psychological realism and presence of the director's superb modern-day character studies, such as Naked or Secrets & Lies. The difference between Peterloo and those four movies is that, when it comes down to it, Peterloo is a bit... dry? I'm the absolute ideal viewer for just about everything going on here (Regency-style diction, leftist agitprop, Mike Leigh shit), and I noticed myself growing a bit impatient every time it became clear that we were in for yet another scene where four different men were going to expound on the same theme, in real time. The great parts of the film are almost unbearably great: in this category I'd put everything involving Nellie and her family, along with the sharp contrast Peake's snappish, irritated line deliveries offers with the ebullience of the radicals or the wheedling we-will-say-everything-but-what-we-mean caution of the politicians (among them Prime Minister Lord Liverpool and Home Secretary Lord Sidmouth, played respectively by Robert Wilfort and Karl Johnson - the latter's wary, sidways way of expressing his character is almost as good a performance as Peake's). The aesthetics are to die for, as well; Suzie Davies's production design, Charlotte Watts's set decoration, and Jacqueline Durran's costumes present 1819 Manchester and the surrounding country with so much wear and tear, so much mud and damp, so much of a pungent shift between the worlds of the working class and nobility, it's easy to forget that this was all constructed, much of it in a computer. And Dick Pope's excellent cinematography, basically re-running the Mr. Turner experiment of using the compositional habits and lighting techniques of early 19th Century English paintings, is already a contender for the prettiest imagery I expect to see in any film released in the U.S. in 2019.

Those are the great parts. The less-great parts? The film's slowness and overall willingness to park and let people talk and talk and talk definitely put up a wall between Peterloo and this viewer, anyway, something that never happened in Topsy-Turvy or Mr. Turner. And despite the outstanding work being done by the cast, the mere fact of how many important characters Peterloo demands we keep track of - and, to the film's inestimable credit, it's almost never a problem keeping all of these people straight - means that Leigh is working with a diluted version of his single greatest strength as a filmmaker. That's his psychological acuity, his films' exquisite ability to watch humans act, and in so doing lay bare all of their deepest feelings, bringing us into the minds and souls of his characters to a degree virtually no other filmmakers, past or present, have ever been able to do at all, let alone do so consistently. The thing about Peterloo is that, ultimately, it's just not a character drama: it's a story in which the rush of cultural change and politics happen to a bunch of characters, all of them finely delineated, to be sure. But politicking, rhetoric, and the conflict between labor and capital are the real stars of the show, and while Leigh is a very good political filmmaker, he's not outstanding at it the way he's outstanding at directing actors. And so, for all its strengths, Peterloo must simply top out at "very good".