Sigourney Weaver will be back home tonight for a special 9/11 performance of The Guys, playing a writer helping a fire captain writing eulogies for his men killed at the World Trade Center. 

"But my heart," the New Yorker said the other day, gently touching her husband, Jim Simpson, on the arm, "will definitely be in Toronto." 

That's because a quickly made -- but thoroughly affecting -- film version of the off-Broadway play, directed by Simpson and starring Weaver and Anthony LaPaglia, will have its world premiere tonight at the Toronto International Film Festival. 

Weaver, who originated the role at Simpson's tiny Flea Theater in Lower Manhattan last December -- opposite her old Ghostbusters pal Bill Murray -- had long ago committed to a free Lincoln Center performance of the piece with Stephen Lang for the anniversary. 

So for the Toronto premiere, LaPaglia will join Weaver's husband, who has been editing the film here to meet the deadline. 

Those who got a first look at The Guys the other day found it a devastatingly straightforward piece of work that goes straight to the heart of what the city was feeling in the days right after Sept. 11. 

Weaver gives a wrenching performance as an Upper West Side journalism professor who volunteers to help a fire captain -- LaPaglia, in a very moving performance -- find the words to describe four of the eight men he lost in the aftermath of the terrorist attack. 

"One of the things that drew me to the play in the first place was that for so many New Yorkers, whether you had lost someone you knew well or not, you felt like you had," Weaver said. 

"We rushed the play into production -- and made the film so quickly -- at least partly because, in a sense, it's a memorial to these four extraordinary human beings." 

Both the play -- which continues its run at the Flea, where Simpson is artistic director -- and the movie were written by Columbia University journalism professor Anne Nelson based on her own experience. 

While the movie preserves the play's two-character dynamic, it opens up the action by providing a pitch-perfect snapshot of the grief-stricken city late last September, including street memorials, a very moving encounter at a coffee shop -- and a climactic funeral filmed at a Brooklyn church with dozens of real-life firefighters. 

Weaver's character is seen interacting with members of her family, including a daughter played by her and Simpson's real-life 12-year-old. 

"It was difficult for our daughter with both of us working on the movie at once," Simpson said. "This was a way of including her." 

"Working with your husband," Weaver joked, "means you can't go home and complain, 'The director wanted me to do something really dumb today.' But I do think Jim brought a sense of truth and balance to the movie." 

The movie was shot in just two weeks this spring on a tight $550,000 budget. 

Actually, it was shot twice -- the first two weeks' footage had be thrown out after it was discovered to be out of focus. 

"That's when it's useful to be married to the star," Simpson said. "She and Anthony were very understanding." 

The independently produced film - which inexplicably won't be shown at the New York Film Festival -- is shopping for an American distributor. 

"We feel an urgency to get it out to the public as soon as possible," Weaver said. "That's why everyone worked so hard to get it done in time for the anniversary."

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