You know Giamatti. He’s the guy with the receding hairline and St. Bernard jowls. His epic, commanding eyebrows put those of Jacks Black and Nicholson to shame. His frumpy, “ordinary-guy” persona populates contemporary cinema screens with regularity, quickly progressing from mainstream supporting roles (“Cinderella Man,” “Saving Private Ryan”) and indie vehicles (“Sideways,” “American Splendor”) to leading-man status (HBO films’ miniseries “John Adams”).

Giamatti’s twitchy, wounded look and manner are deeply, painfully human. Some might consider his rumpled, short-and-stocky profile to be homely. But there’s charming, cuddly charisma as well. Film Threat critic Whitney Borup recently wrote, “Could it be that I am one of the few twenty-somethings in the world that finds him and those snaggly teeth a bit sexy?”

Meanwhile, guys relate to his Average Joe appearance and uninhibited acting chops. Merrily unleashing his id in “Shoot ‘em Up” as the villainous Hertz, Giamatti is so animated and twitchy, we revel in his amoral mayhem. It’s contagious anarchy. Even though he’s not beyond running down infants and fondling female corpses, we kind of… like this guy.

There’s also the anxiety-plagued, defeated flip side of Giamatti’s resume, where he plays depressed, troubled losers. But are they really losers? The cranky neurotics from “Sideways” and “American Splendor” might have problems, but we feel for them. We are them. We kind of like these guys, too.

A perky blonde publicist approaches me with tentative steps. “I’m sorry,” she announces, her strained eyebrows conveying worry. “The interview has been delayed slightly. Paul has to complete a photo shoot."

No big deal, I tell her. In fact, the extra few minutes provide an opportunity to watch Giamatti outside the formal trappings of a press junket. Sporting a moss green polo shirt and casual jeans, Giamatti stands patiently with hands in pockets as busy shutterbugs assemble lighting rigs and load cameras.

“Do something in character,” suggests one of the cameramen. “Maybe the eyebrows.”

With arms crossing chest, Giamatti lifts an eyebrow. The visual likeness is that of a teddy bear nursing a grudge. The cameraman chuckles, then snaps a few shots. He’s getting what he wants.

The photo shoot’s esteemed subject, however, is clearly not getting what he wants. “I’m gonna go downstairs and have a smoke,” Giamatti announces to the crew.

With the main attraction outside on Fourth Street to savor a ciggie, I’m left staring at a state-of-the-art jumble of photography equipment. What’s the towering, six-foot long apparatus that resembles a beach umbrella? Meanwhile, why is the assistant holding a strip of aluminum-tinted fabric? The metallic accessories, with their cold hues of silver and black, give the whole affair a vaguely futuristic vibe.

Except, of course, for Giamatti. Considerably less fidgety after returning from his smoke break, the actor hunches forward and stares at his shoes while a busy cameraman shoots roles of film.

This strange contrast between earthy, lived-in humanity and ultramodern technology is fitting for the occasion. Giamatti’s in town to promote “Cold Souls,” a bizarre science fiction fable by first-time feature director Sophie Barthes. “Cold Souls” presents a world both philosophical and whimsical, melding the futuristic playfulness of Woody Allen’s “Sleeper” with the off-kilter eccentricity of Charlie Kaufman (“Eternal Sunshine of the Spotless Mind”).

The film’s outrageous setting is a parallel universe very similar to our own – with a few ahead-of-our-time perks. Forget calling Dominoes for a home-delivery pizza. Why not thumb through the Yellow Pages for a Soul Storage clinic, and make an appointment to extract your troubled, weary essence?

In “Cold Souls,” Giamatti plays...Paul Giamatti. But is the actor truly playing himself? During a pre-movie Q&A at Seattle’s Harvard Exit Theater two days earlier, a SIFF viewer asked this very question. “I kinda hope not,” the celebrated actor responded with a nervous chortle. “I play him as an uptight, New York actor who just happens to have my name.”

Giamatti’s tormented thespian is attempting to survive an especially grueling stage production of “Uncle Vanya.” The emotionally draining, overwhelming play is sapping him of sanity.

Desperate for change, this depressed burnout discovers a state-of-the-art “soul removal” clinic. In need of a psychic tune-up? Time for an internal oil change? No problem. The efficient Dr. Flintstein (David Strathairn) can facilitate a spiritual second wind by extracting your chickpea-sized soul, and even replacing it with that of a more appealing donor. Maybe a Russian poet, or Al Pacino.

According to Barthes, a petite, pregnant brunette, the “Cold Souls” concept appeared to her in a dream. “I was standing in a soul removal clinic,” she describes. “Woody Allen was there, basically playing Paul’s role from the film. I thought the dream was so absurd and funny that I felt it could be a narrative for a whole movie.”

Reclining in a chair to my left in a festival press room, Barthes is accompanied by her significant other, “Cold Souls” cinematographer Andrij Parekh. Meanwhile, Giamatti peers towards me from across a sprawling black table cluttered with glass cups and water pitchers.

“It’s funny,” he remarks of Barthes’ nocturnal vision for “Cold Souls.” “So often, I’ll have a dream and go, ‘Wow. That would make a cool movie.’ Then when I really think about it, it doesn’t really make any sense.”

He chuckles, then continues this thought pattern. “But this was a seamless idea. It’s really weird how fully formed it is.”

In the film, Giamatti’s frustrated thespian proceeds with the soul extraction. As with most medical procedures, however, there are side effects. The now-soulless actor finds himself unable to practice his chosen craft. When he’s called on to be downbeat and serious, an out-of-character giddiness is prompted. Libidinous lust kicks into overdrive, as evidenced by his shameless goosing of a female stage-sharer during play rehearsals. The serious pathos required for “Uncle Vanya” is gone with the wind.

What is a soul? And how would we behave differently without one? According to Barthes’ film, soul extraction snuffs out insight, emotional range, and deep thinking, while amping up the more base, id-fueled human tendencies. It’s an easier way to live, perhaps – but without the dynamic palette of yearnings, guilt, pain, and triumph inherent to the human condition. Call it a lobotomy lite.

Not a condition well suited for those employed to convey larger-than-life emotions on stage and screen. Perhaps, reflects Giamatti’s character, he should have been more careful about what he wished for. Despite being a catalyst for sometimes-unpleasant human conditions such as regret, grief, and despair, perhaps the human soul is necessary for living a self-actualized life.

Plans to reverse the extraction are complicated by a Russian soul-smuggling ring, where a spoiled, aspiring-actress wife has stolen Giamatti’s conflicted soul and claimed it as her own (she mistakenly thought it belonged to Al Pacino). With the help of Olga, a secretive Russian blonde with a Deborah Harry haircut, will Giamatti retrieve both his chickpea soul – and his impassioned acting chops?

Considering the dreamlike themes that define “Cold Souls,” it’s fitting that Barthes’ landing of Giamatti for her film is straight out of a fairy tale. The 2006 Nantucket Film Festival provided a means for both talents to intersect. Giamatti was in attendance to promote “The Illusionist,” and present an award to “Sideways” collaborators Jim Taylor and Alexander Payne. Meanwhile, Barthes was present to receive the Nantucket Film Festival Showtime Tony Cox Award for her not-yet-filmed “Cold Souls” screenplay.

The director approached the actor about starring in a film based on her prizewinning story. “He was giving an award, and I was receiving one,” explains Barthes. “The circumstances were right.”

I ask Giamatti and Barthes if this type of collaboration is common. After all, isn’t agent-to-actor the typical channel of distribution for percolating productions? How often does a relatively unknown filmmaker get to query her story straight to the source?

“I don’t know,” Giamatti responds, running a hand through his red, curly beard. “I mean, I know that I’ve had a lot of people hand me scripts. But most of them are not very interesting. This one was such an intriguing idea, I was eager to read the script. But I doubt that it happens a whole lot. I can’t imagine it does.”

“Maybe with people at a higher level,” suggests Barthes, “with an established director approaching a famous actor. But I was a first time director.”

“It’s a tribute to how strong the idea was,” said Giamatti. “I can remember getting the script and telling my manager about it. And she responded strongly. Every time somebody heard the idea, they took to it immediately. The script was different than most of the things I get handed.”

“Cold Souls” owes much to early Woody Allen. Flintstein’s stark-white office boasts a milk-colored, radiotherapy-style soul-removal machine and other marshmallowy contraptions reminiscent of the “Sleeper” orgasmatron. During a later sequence based in Russia, the bleak, industrial look of “Cold Souls” suggests Terry Gilliam’s “Brazil.” Thanks to cinematographer Andrij Parekh, the film’s imagery toggles between real and dreamlike, while remaining visually seamless and convincing.

I ask Parekh what prompted him to stay away from trendy, CGI-based special effects, in favor of these relatively sparse – yet strikingly atmospheric – sci-fi sets. “It made it more believable that this could actually happen,” he explains. “This giant, extravagant CGI requires such a leap of faith.”

“We couldn’t have afforded expensive effects anyway,” adds Giamatti. “But also I love science fiction movies that are filmed in actual locations, with sets that are based in reality.”

“Dr. Flinstein’s soul storage place was an elementary school,” reveals Parekh. “We took out some walls, but the ceiling was native to the space.”

“Later on, there’s a Russian soul removal place. It was actually a warehouse in Brooklyn, filled with all these incredible machines,” adds Giamatti. “They didn’t have to do anything to it, except to add the soul extractor.”

“And it was the same (soul extractor from Flintstein’s lab), just painted gray,” admits Barthes. “When you don’t have money, you have to be inventive.”

“It’s a great idea that the Russian machine is a little crappy,” suggests Giamatti, now laughing and exposing those snaggly teeth admired by Borup. “It was a little sketchy. Instead of the nice glistening, shining white, it’s kinda crappy looking. I feel like that always works better with science fiction.”

Outside the press room window, downtown Seattle is abuzz with caffeinated weekend energy. Four blocks west is the Pike Street Market, where seafood vendors toss Copper River Salmon to buyers, and the original Starbucks coffee shop serves up gallons of java to thirsty tourists. Giamatti shares a special connection to the area, having cut his teeth performing at the Annex Theatre from 1989 to 1992.

“I remember playing a lot of psychos,” he reflects on the Annex days. “If they needed a guy to pull his pants down, they’d call on me.

“It still exists. I mean, it’s still here, the Annex, which is great. It was a little theatre that these guys I know had started in a barn on Vashon Island. They eventually got a space on Fourth Avenue. It was this little, black box theatre. They did a lot of original stuff. We did weird adaptation of (Luigi) Pirandello plays. We did really crazy stuff. I played old men. If you needed an old man, or a psycho, I was there to do it. Played psychos for years.”

These days, it’s a different game entirely. Giamatti is A-list now. In fact, it’s ironic that the “Cold Souls” running joke is that in Russia, nobody recognizes the actor. While on location is St. Petersburg, however, Giamatti was met with unexpected adoration. During meals, fellow diners expressed their admiration by sending bottles of wine to the star’s table. “I think it was because of ‘The Illusionist,’” he explains. “People really liked that movie over there. It was surprising, and kind of a trip.”

The interview winds down. Hands are shaken. Leaving the press room, I ask Giamatti about the photo shoot preceding our conversation. “You know,” he confesses, “I’m actually kind of uncomfortable having my picture taken. It’s okay in movies, but…”

I tell him I noticed the trademark “eyebrow raising” pose at one point, to which he comments, “People like that. I guess it’s considered ‘iconic.’”

Then, Giamatti bolts for the elevator, appearing somewhat anxious. But it’s not his soul that’s bothering him.

He’s out of cigarettes.