JOINED AT THE HIP: Louis Pepe, far left, and Keith Fulton, far right, with Harry and Luke Treadaway.

Temple grad students when Terry Gilliam hand-picked them to document the making of 12 Monkeys, Fulton and Pepe put themselves on the map with 2002's Lost in La Mancha, a chronicle of Gilliam's cataclysmic attempt to produce an adaptation of Don Quixote. Felled by bad weather, shaky financing and an arthritic leading man, Gilliam's Quixote collapsed in a heap, and Fulton and Pepe captured every gory detail.

Four years later, they've got their first fiction feature in the can, an ersatz documentary with a subject so odd it might even give Gilliam pause. Flashing back to the British glam rock scene of the 1970s, Brothers of the Head unravels the story of Tom and Barry Howe, conjoined twins picked to front their own band by a fading vaudeville impresario. Through talking-head interviews and flawlessly faked vintage footage (shot by veteran cameraman Anthony Dod Mantle), the film chases after but never quite catches up with its elusive subjects, who remain as enigmatic at the movie's end as at its beginning.

Adapted by frequent Gilliam collaborator Tony Grisoni from a Brian Aldiss novella, Brothers is hardly a high-concept proposition. Far from the Behind the Music parody one might expect, it's a moody psychodrama with disturbing, ambiguous undertones. "The goal is to leave the audience dumbfounded," Fulton says, "and I think we succeed."

Of course, there's that premise to get past first. Both Fulton and Pepe are aware that the movie's subject matter lends itself to caricature. "It sounds like the stupidest thing in the world," Fulton admits, "and yet the whole thing started to be very meaningful to me. You're taking this very extreme, freakish example, and finding all kinds of meaning in it."

Indeed, the Howe brothers, played by fraternal twins Luke and Harry Treadaway, can be seen as a four-legged embodiment of any number of things, from the sexual exhibitionism of glam to rock's history of producing bands fronted by feuding siblings (c.f. The Kinks, whose early singles serve as a crucial teaching tool). But at heart, Brothers of the Head is a movie about the nature of collaboration, particularly when it goes beyond being merely professional. "I don't know if people who don't know us see it," Fulton says, "but people who do know us know what a personal thing it is for us. Our relationship is maybe not as intense as being physically conjoined, but it's pretty intense."

Brothers conveys only the slightest sense of how Tom and Barry exist outside the confines of The Bang Bang, the name given to their prefab band. The boys are mysteriously absent from the present-day interview segments, and the only hints of their upbringing are snippets from a purportedly unfinished Ken Russell biopic. (Russell himself shows up to authenticate the footage.) The first time we see them, pensive Tom is learning to play the guitar, while his brother Barry works on his Lydonesque sneer. In a sense, they're always on display, a feeling the movie amplifies by drawing attention to the presence of Tom Bower's prying documentarian. At one point, the camera peers through a doorway and finds the brothers naked, bathing each other and drenched in Caravaggio light.

As Pepe told a packed house at last fall's Toronto Film Festival, "When you strap two good-looking 20-year-olds to each other, a certain subtext starts to emerge." Fulton admits that "we took every opportunity to amp up the homoerotic vibe, because that does interest us," although Pepe points out that Grisoni's script contains the pivotal scene where the brothers, seeking a shocking image for their album cover, spontaneously French-kiss each other.

But Grisoni's script ended up being no more than a blueprint for the finished film. Adapting documentary techniques to a fiction setting, Fulton and Pepe encouraged their actors to improvise whenever possible, rehearsing the moments before and after a scene but not touching the scene itself until the cameras were rolling. "By the time the actors hit the set, they were very familiar with the purpose of the scene," Fulton says. "But we never told them, 'You have to hit that line at that point.'"

The desire to keep things unpredictable proved especially tricky when it came to directing the Treadaways. "We don't have a style where we like one actor to know what the other is going to do," Fulton says. "So Lou and I were frequently seen on set, him whispering in one ear and I was whispering into the other." Fulton calls it "conjoined direction." On the set, Pepe says, their roles are flexible, like the Five Chinese Brothers, "where whichever brother was most suited to the torture at hand was the one who went to it. People ask us, 'How do you direct a movie with someone else,' but we came out of this wondering how anyone does it alone."

As The Bang Bang becomes more successful, the brothers' personalities diverge. Barry grows more withdrawn and sullen, while Tom shaves his hair into a proto-mohawk and starts baiting the audience from the stage. The pressure of their bond intensifies: Tom mimes severing "the join" that connects them, while Barry writes a song whose chorus concludes, "Are you you or are you me?"

Pepe points out that the fear of losing one's identity is hardly unique to working partnerships. He recalls watching a documentary about Reading, Pa.'s Schappell sisters, a pair of conjoined twins attached at the head. "They were following them around New York, and then going up and interviewing all the people who were staring at them," Pepe recalls. "They interviewed this old married couple, and the woman is saying, 'I don't understand it. How do people live that way?' And the husband kept picking up and completing her sentences. They're standing there saying they don't understand this kind of codependence, and yet they don't realize it's not very far off from their own."

"In the contemporary world," Pepe continues, "people think a relationship is me and you. But we wanted to explore that the idea is a thing in itself—a union that is greater than the sum of its parts. The film touches on different people's attempts to explain what it is. Is it the join? Is it the creative collaboration? All of these people are exploring a relationship that, on a basic, fundamental level, none of them will ever be able to understand."

"The nature of collaboration, in any art form, is that you are often sacrificing your own agenda to fashion a joint agenda," Pepe says. "When you hit certain bumpy spots, you find yourself questioning, 'Have I lost my identity entirely to this collaboration?'"

"Yes," Fulton chimes in. "You have."

Brothers of the Head screens Fri., March 31, 5:30 p.m., at the Bridge and Sat., April 1, 10 p.m. at Ritz Five. Fulton and Pepe will attend both screenings.

"Mystique" is a word that often turns up when discussing the Quays, not least because their works are set in precisely that part of the creative universe where words become more of a hindrance than a help. One can say that The Piano Tuner of Earthquakes is the Quays' second feature film, that it takes place on a remote island ruled by the mysterious Dr. Droz (Gottfried John), that he has kidnapped and perhaps murdered an opera singer (Amira Casar) whose voice he thinks will give life to his stillborn compositions, and that he hires a celebrated piano tuner (César Seracho) to calibrate not instruments but automata, curious biomechanical devices dotting the island which play some part in Droz's plan to resuscitate the singer. But that doesn't go far toward explaining the movie's gauzy, hallucinatory texture, or its mixture of mild portentousness, dry humor and fairy-tale dislocation.

The Quays are best known for their stop-motion animated short films, including The Cabinet of Jan Svankmajer, a tribute to the great Czech puppet animator, and the unnerving Street of Crocodiles, an adaptation of Bruno Schulz's The Cinnamon Shops. But in the mid-1990s, after shooting their first live-action feature, Institute Benjamenta, the Quays' traditional financing sources, mainly European TV channels with commissioning budgets, dried up, and they went five years without producing a single film. "The only way we can do animation is if we do a feature film," the Quays say. "You cannot get funding for short animation."

The brothers are surprisingly frank about their mixed feelings for Piano Tuner. Piecing together their $3.5 million budget from various funding sources involved a series of barely compatible compromises, as when a British funder demanded the script be made more commercial, and the French and German sources who had already approved the script balked at any alterations. "For us, the film is problematical because of this outside influence," they say. "Too many fingers spoil the soup."

Other conditions are harder to fathom, such as the contractual requirement that the film run no longer than 95 minutes, the result of which is that sequences that might have explained the movie's elusive story ended up on the cutting-room floor. But the Quays are at least partly pleased with the latter development. "It eludes more people, but it also makes it interesting, more abstract," they say. "Maybe it's a good thing, trying to musicalize it and shirk the narrative."

TOGETHER ALONE: Stephen and Timothy Quay with Amira Casar on set.

The Quays have often used music as the starting point for their short films, and indeed, it helps to approach Piano Tuner as you would a piece of music, distinguishing themes and their variations rather than scrabbling for shreds of plot and character. Apart from Gottfried John, who infuses his character with a wicked lustfulness, the performances are precise to the point of frigidity, to the point where the humans seem less expressive than the puppets that populate the movie's occasionally jarring animated interludes. But then, that's clearly the point—just as Droz's automata test the boundary between the mechanical and the living, so the island seems to mechanize its human inhabitants, especially the gaggle of undifferentiated humanoids (the Quays call them "gardeners") whose actions seem to serve some unknown ritual. "We wanted a genuine contamination between the puppet realm and the live action realm, perhaps subverting it, or oozing into or sucking away at it, and vice versa," they explain. To that end, they "use our actors more like you would in a ballet. They're always integrated with the music, the decor, the architecture. It's a stylized universe, and it isn't psychological cinema."

"When you make a fairy tale," they continue, "you create types, rather than deeply involved psychological characters. It's the ogre, or the sleeping beauty. You have to observe it through a telephoto lens, tell the story in an equally dreamlike or dark mode, but at a deeper remove. It's like when you watch Noh theater, the power of the mask. The mask doesn't tell you what it's thinking—I have to read by the slight tilt of the head. It's in that realm that puppets work great."

The Quays make it sound as if working with actors is the natural culmination of their career. "We were always fascinated by live action," they say. "It was just a question of building up the confidence." But it's clear that animation is their first love. "Animation really does inhabit a special world that has nothing to do with live action drama," they say. "Just establishing such a powerful, tactile, concrete world, it creates an otherness that is very important to us. It has no laws to obey."

Part of the thrill of animation is the liberty that working as a two-man crew in the studio provides. "It's a real laboratory situation," they say. "Suddenly you discover something when you're building the set that takes you left instead of right, and you bend accordingly." Not surprisingly, such spontaneity was harder to come by on the Piano Tuner set. "Exactly the thing that most upset us about doing a feature was that, with a crew of 44, you can't afford to be spontaneous. You've got a script that is being looked at, conceived from on high, whereas if we're in the studio, we can just say, 'That's crap; let's reinvent this.' A feature film is not a laboratory—it's an execution platform. Here, we can be intuitive. There, we can't."

Surprisingly given their antiquarian sensibilities (several vintage clocks chime during our hourlong talk), the Quays have abandoned shooting on film due to the expense. (2000's In Absentia was their last 35 mm project.) If the notion of the Quays editing on Final Cut Pro is slightly disorienting, they seem genuinely energized by the possibilities—especially the notion that shooting on HD might allow them to keep all those fingers out of the soup.

The Piano Tuner of Earthquakes screens Fri., April 7, 5 p.m at Ritz Five and Sat., April 8, 9:45 p.m. at the Bridge.